Memory sizes of Microsoft Windows Operating Systems (Arnoud J.G. Mulder, v1:20050106 v5:20110614)
Windows Version
Support boot.ini options
Maximum addressable physical memory
Maximum 32bit application
address-space
/PAE
/3GB
/USERVA
Windows NT3.51 Workstation
Windows NT3.51 Server
N
N
N
N
N
N
4GB
4GB
4GB
4GB
n/a
n/a
n/a
n/a
2GB
2GB
n/a
n/a
n/a
n/a
n/a
n/a
Windows NT4 Workstation
Windows NT4 Server
Windows NT4 Enterprise
N
N
N
N
N
Y
N
N
N
4GB
4GB
4GB
4GB
4GB
4GB
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
2GB
n/a
n/a
3GB
n/a
n/a
n/a
n/a
n/a
n/a
Windows 2000 Professional
Windows 2000 Server
Windows 2000 Advanced Server
Windows 2000 DataCenter
N****
N****
Y
Y
Y
Y
Y
Y
N
N
N
N
4GB
4GB
8GB
32GB
4GB
4GB
4GB
4GB
n/a
n/a
8GB
32GB
n/a
n/a
8GB
16GB
2GB
2GB
2GB
2GB
n/a
3GB
3GB
3GB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Windows XP Starter Edition
Windows XP Home Edition
Windows XP Professional
Windows XP Professional
Windows XP Professional
N****
N****
N****
n/a
n/a
?
Y
Y
n/a
n/a
?
N
N
n/a
n/a
512MB
4GB
4GB
128GB
128GB
512MB
4GB
4GB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
2GB
2GB
2GB
?
3GB
3GB
4GB*
4GB*
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
x64
IA64
Windows Home Server
default
/PAE
/PAE
/3GB
default
/3GB
/USERVA
Max. 64bit
application
address-space
Max.
by design
N
Y
N
4GB
4GB
n/a
n/a
2GB
3GB
n/a
n/a
N****
N****
N****
N****
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
4GB
4GB
4GB
4GB
64GB
64GB
64GB
64GB
64GB
64GB
64GB
64GB
4GB
4GB
4GB
4GB
4GB
4GB
4GB
4GB
4GB
4GB
4GB
4GB
n/a
n/a
n/a
n/a
64GB
64GB
64GB
64GB
64GB
64GB
64GB
64GB
n/a
n/a
n/a
n/a
16GB
16GB
16GB
16GB
16GB
16GB
16GB
16GB
2GB
2GB
2GB
2GB
2GB
2GB
2GB
2GB
2GB
2GB
2GB
2GB
3GB
3GB
3GB
3GB
3GB
3GB
3GB
3GB
3GB
3GB
3GB
3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Windows 2003 Server Enterprise RTM IA64
Windows 2003 Server Enterprise SP1 IA64
Windows 2003 Server Enterprise SP2 IA64
Windows 2003 Server DataCenter RTM IA64
Windows 2003 Server DataCenter SP1 IA64
Windows 2003 Server DataCenter SP2 IA64
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
512GB
1TB
2TB
512GB
1TB
2TB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
2GB
2GB
2GB
2GB
3GB*
4GB*
4GB*
3GB*
4GB*
4GB*
n/a
n/a
n/a
n/a
n/a
n/a
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
Windows 2003 Server Standard SP1
Windows 2003 Server Standard SP2
Windows 2003 Server Standard R2
Windows 2003 Server Enterprise SP1
Windows 2003 Server Enterprise SP2
Windows 2003 Server Enterprise R2
Windows 2003 Server DataCenter SP1
Windows 2003 Server DataCenter SP2
Windows 2003 Server DataCenter R2
x64
x64
x64
x64
x64
x64
x64
x64
x64
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
32GB
32GB
32GB
1TB
1TB
1TB
1TB
1TB
1TB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
2GB
2GB
2GB
2GB
2GB
2GB
2GB
4GB*
4GB*
4GB*
4GB*
4GB*
4GB*
4GB*
4GB*
4GB*
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
Windows 2003 Web Edition
Windows 2003 Small Business Server
Windows 2003 Storage Server
Windows 2003 Storage Srv Enterprise
Windows 2003 Compute Cluster Srv
IA64
Y
Y
Y
Y
n/a
Y
Y
Y
Y
n/a
Y
Y
Y
Y
n/a
2GB
4GB
4GB
8GB
32GB
2GB
4GB
4GB
4GB
n/a
2GB
4GB
4GB
8GB
n/a
2GB
4GB
4GB
8GB
n/a
2GB
2GB
2GB
2GB
2GB
3GB
3GB
3GB
3GB
4GB*
2-3GB
2-3GB
2-3GB
2-3GB
n/a
n/a
n/a
n/a
n/a
2GB/8TB**
Windows Vista Starter
Windows Vista Home Basic N (EU)
Windows Vista Home Basic
Windows Vista Home Premium
Windows Vista Business N (EU)
Windows Vista Business
Windows Vista Enterprise
Windows Vista Ultimate
?
Y***
Y***
Y***
Y***
Y***
Y***
Y***
?
Y***
Y***
Y***
Y***
Y***
Y***
Y***
?
Y***
Y***
Y***
Y***
Y***
Y***
Y***
1GB
4GB
4GB
4GB
4GB
4GB
4GB
4GB
?
4GB
4GB
4GB
4GB
4GB
4GB
4GB
?
4GB
4GB
4GB
4GB
4GB
4GB
4GB
?
4GB
4GB
4GB
4GB
4GB
4GB
4GB
?
2GB
2GB
2GB
2GB
2GB
2GB
2GB
?
3GB
3GB
3GB
3GB
3GB
3GB
3GB
?
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
8GB
8GB
16GB
128GB
128GB
128GB
128GB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
2GB
2GB
2GB
2GB
2GB
4GB*
4GB*
4GB*
4GB*
4GB*
4GB*
4GB*
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
Y
Y
Y
Y
Y
Y
?
?
?
4GB
64GB
64GB
4GB
4GB
4GB
4GB
64GB
64GB
?
?
?
2GB
2GB
2GB
3GB
3GB
3GB
2-3GB
2-3GB
2-3GB
n/a
n/a
n/a
Windows 2008 Itanium-based Systems IA64
Windows 2008 Itanium-based R2
IA64
n/a
n/a
n/a
n/a
n/a
n/a
2TB
2TB
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
4GB*
4GB*
n/a
n/a
2GB/8TB**
2GB/8TB**
Windows 2008 Server Foundation R2
Windows 2008 Server Standard
Windows 2008 Server Standard R2
Windows 2008 Server Enterprise
Windows 2008 Server Enterprise R2
Windows 2008 Server Datacenter
Windows 2008 Server Datacenter R2
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
8GB
32GB
32GB
1TB
2TB
1TB
2TB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
2GB
2GB
2GB
n/a
n/a
4GB*
4GB*
4GB*
4GB*
4GB*
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
Y
Y
Y
Y
?
?
4GB
4GB
4GB
4GB
4GB
4GB
?
?
2GB
2GB
3GB
3GB
2-3GB
2-3GB
n/a
n/a
Windows 2003 Server Standard RTM
Windows 2003 Server Standard SP1
Windows 2003 Server Standard SP2
Windows 2003 Server Standard R2
Windows 2003 Server Enterprise RTM
Windows 2003 Server Enterprise SP1
Windows 2003 Server Enterprise SP2
Windows 2003 Server Enterprise R2
Windows 2003 Server DataCenter RTM
Windows 2003 Server DataCenter SP1
Windows 2003 Server DataCenter SP2
Windows 2003 Server DataCenter R2
Windows Vista Home Basic N (EU)
Windows Vista Home Basic
Windows Vista Home Premium
Windows Vista Business N (EU)
Windows Vista Business
Windows Vista Enterprise
Windows Vista Ultimate
x64
x64
x64
x64
x64
x64
x64
Windows 2008 Server Standard
Windows 2008 Server Enterprise
Windows 2008 Server Datacenter
x64
x64
x64
x64
x64
x64
x64
Windows 2008 Web server
Windows 2008 Small Business Server
Windows 2008 Web server
Windows 2008 Small Business Server
Windows 2008 Server HPC Edition
x64
x64
x64
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
32GB
32GB
128GB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
2GB
4GB*
4GB*
4GB*
n/a
n/a
n/a
2GB/8TB**
2GB/8TB**
2GB/8TB**
Windows 2008 Web server
Windows 2008 Server HPC Edition
x64
x64
n/a
n/a
n/a
n/a
n/a
n/a
32GB
128GB
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
4GB*
4GB*
n/a
n/a
2GB/8TB**
2GB/8TB**
Windows 7 Starter
Windows 7 Home Basic
Windows 7 Home Premium (N)
Windows 7 Professional (N)
Windows 7 Enterprise (N)
Windows 7 Ultimate (N)
?
Y***
Y***
Y***
Y***
Y***
?
Y***
Y***
Y***
Y***
Y***
?
Y***
Y***
Y***
Y***
Y***
2GB
4GB
4GB
4GB
4GB
4GB
?
4GB
4GB
4GB
4GB
4GB
?
4GB
4GB
4GB
4GB
4GB
?
4GB
4GB
4GB
4GB
4GB
?
2GB
2GB
2GB
2GB
2GB
?
3GB
3GB
3GB
3GB
3GB
?
2-3GB
2-3GB
2-3GB
2-3GB
2-3GB
n/a
n/a
n/a
n/a
n/a
n/a
Windows 7 Starter
Windows 7 Home Basic
Windows 7 Home Premium (N)
Windows 7 Professional (N)
Windows 7 Enterprise (N)
Windows 7 Ultimate (N)
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB
8GB
16GB
192GB
192GB
192GB
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
2GB
2GB
2GB
2GB
2GB
2GB
4GB*
4GB*
4GB*
4GB*
4GB*
4GB*
n/a
n/a
n/a
n/a
n/a
n/a
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
2GB/8TB**
* in 64bit Windows no /3GB switch is needed in the boot.ini. But the 4GB virtual addressspace in 32bit applications is only available if
IMAGE_FILE_LARGE_ADDRESS_AWARE is set in it’s executable header. Otherwise the virtual addressspace is limited to 2GB.
In Windows 2003 before SP1 the virtual addressspace is max 3GB instead of 4GB.
** A 64 bit process normally has a limit of 2GB virtual addressspace. But when IMAGE_FILE_LARGE_ADDRESS_AWARE is set in it’s
executable header the addressspace is 8TB for Intel-based systems (and 7TB for Itanium-based/IA64 systems).
*** On Vista the /PAE and /3GB boot.ini parameters are not supported. Use the “BCDEdit /set” command instead to set boot-options:
BCDEdit /set increaseuserva Megabytes
(replaces /3GB and /USERVA)
BCDEdit /set pae [ Default | ForceEnable | ForceDisable ] (replaces /PAE)
Note that the addressspace is limited to 4GB by design even if /PAE is enabled, only use for PAE switch is AWE bankswitching
**** Not sure whether /PAE isn’t supported. But because addressspace is limited to 4GB there is no use of /PAE anyway, except for use of
AWE bankswitching from an application.
Boot.ini options:
/3GB
enable that applications can use a virtual address space of 3GB. The system only uses the upper 1GB range for system calls
instead of 2GB.
/3GB on “Windows 2000 Professional” and “Windows 2000 Server” has the effect of reducing kernel size to 1 GB while the
application address-space stays 2 GB.
Application must have IMAGE_FILE_LARGE_ADDRESS_AWARE in its header to get an 3GB address-space.
This is for backward compatibility with old programs which compare pointers (pointers are signed)
Some DLL’s load at 2GB boundary (0x7FFFFFFF and below). This makes it impossible to have an continues address-space
above 2GB. A VirtualAlloc above 2GB will fail therefore.
It looks like anno 2011 Microsoft calls 3GB, 4GT instead (4-gigabyte tuning)
/PAE
Enable enhanced adressing mode (36bit physical addressing mode, max 64GB theoretically)
Minimum processor for PAE: Intel Pentium Pro (AMD x64)
/USERVA: reduce the user-address-space from 3GB downto 2GB to leave more memory for the kernel
Why less than 4GB is seen by 32-bit Windows XP (and other 32-bit OS which support max 4GB and no PAE)
An Intel-architecture processor (AMD included) maps I/O ports onto memory addresses. In the design of the PC the PCI/AGP I/O is started
from address 0xFFFFFFFF and lower addresses. The 0xFFFFFFFF is the max address of 32bit (4GB). The size of this I/O address range
is depends on the detailed design of the motherbord, BIOS and of the present PCI/AGP cards.
Memory at these I/O address range cannot be addressed. Modern motherboards have a remapping option so the memory located at the
I/O addresses is moved to addresses above the 0xFFFFFFFF (4GB) address. Unfortunately 4GB-32bit-Windows versions (like XP) is not
able to address memory located above the 4GB boundary, now for another reason as the kernel uses 32bit words for addressing.. With
PAE (uses 36bit adresses) addressing is possible but PEA is not supported by the 4GB-versions of Windows.
Take for example a ASUS M2N motherboard with 8GB memory with a Geforce 8500 PCI-e card and 3 SATA x4 controllers.
The remapping option can be found at BIOS->Advanced->Chipset->Memory controller->Memory configuration->Memory hole remapping.
The I/O on this motherbord is located from 0x9FF49000 to 0xFFFFFFFF. Only the first 2683604992 bytes of memory can addressed below
the 4GB boundary. The remapping option remaps the memory between 0x9FF49000-0xFFFFFFFF to the addresses 0x1000000000x1600B7000. We see the following:
Memory reported by BIOS
Memory reported by Windows XP
Memory reported by 64bit (or 32bit-with-PAE)
-
Disabled remapping
6656MB
2559MB (2683604992 byte)
6654MB (6977695744 byte)
Enable remapping
8192MB
2559MB (2683604992 byte)
8190MB (8588308480 byte)
Without remapping 1536MB of memory is not seen by the BIOS as it is located at I/O addresses
Remapping makes no difference for 4GB-32bit Windows as the remapped memory is out of reach. Always 1536MB is unused.
On 64bit Windows or 32bit Windows with PAE the remaping results in 8GB of available memory (ca. 2MB less because of
resevered kernel and BIOS memory).
Methods of using large memory from within an 32 application:
1 – Specify /3GB in boot.ini and link application with IMAGE_FILE_LARGE_ADDRESS_AWARE. Use Windows versions which support
PAE (Windows 2003 or equivalent). Then the virtual address spaces is increased from 2GB to theoretically 3GB. Practical you end up with
two separate address ranges. Below address 0x8000000 you have about 1.5 GB and above it about 1 GB. In total 2.5 GB. Spanning your
tasks over multiple processes and using interprocess communication you can use as much memory as possible. Note that the overhead for
LDT’s with 4KB page size wastes a lot of memory (hundreds of MB).
2 – Use of AWE is very slow because it takes a lot of time to reload the LDT tables while switching the bank. (page size is only 4GB).
Misc background information:
Europe Vista versions do not have media player and media API’s (and that last one makes them unusable of course)
A 64bit application’ virtual addressspace is 8TB (althrough 64bit could address 16777216 TB = 16 EB). Microsoft only reserves a
“small” part of the total possible addressspace for applications, because it is so “unbelievable” large… well, the future will tell…
There is no 32bit version of Windows Compute Cluster Server 2003
There are no 64bit versions of Windows 2003 Small Business Server, Windows 2003 Server Web Edition, Windows 2003 Storage
Server, Windows 2003 Storage Server Enterprise Edition
Availability of AWE API (bankswitching from within an application in combination with PAE, AWE is useless without PAE)
Windows Version
AWE API
PAE support
Windows NT4 Workstation
Windows NT4 Server
Windows NT4 Enterprise
N
N
N
N
N
N
Windows 2000 Professional
Windows 2000 Server
Windows 2000 Advanced Server
Windows 2000 DataCenter
Y
Y
Y
Y
N
N
Y
Y
Windows XP Home Edition
Windows XP Professional
Y
Y
N
N
Windows 2003 Server Standard
Windows 2003 Server Enterprise
Windows 2003 Server DataCenter
Y
Y
Y
N
Y
Y
Version numbers (via GetVersionEx with OSVERSIONINFOEX)
Windows. 3.1 with WIN32s
Windows. 3.11 with WIN32s
3.01
3.11
VER_PLATFORM_WIN32s
VER_PLATFORM_WIN32s
Windows 95
Windows 98
Windows Me
4.00
4.10
5,00
VER_PLATFORM_WIN32_WINDOWS
VER_PLATFORM_WIN32_WINDOWS
VER_PLATFORM_WIN32_WINDOWS
Windows NT 3.1
Windows NT 3.51
Windows NT 4.0
Windows 2000
Windows XP
Windows Server 2003
Windows Server 2003 R2
Windows Vista
Windows Server 2008
3.01
3.51
4.00
5.00
5.01
5.02
5.02
6.00
6.00
VER_PLATFORM_WIN32_NT
VER_PLATFORM_WIN32_NT
VER_PLATFORM_WIN32_NT
VER_PLATFORM_WIN32_NT
VER_PLATFORM_WIN32_NT
VER_PLATFORM_WIN32_NT
VER_PLATFORM_WIN32_NT
VER_PLATFORM_WIN32_NT
VER_PLATFORM_WIN32_NT
GetSystemMetrics(SM_SERVERR2) == 0
GetSystemMetrics(SM_SERVERR2) != 0
OSVERSIONINFOEX.wProductType != VER_NT_WORKSTATION
OSVERSIONINFOEX.wProductType == VER_NT_WORKSTATION
- GetNativeSystemInfo indicates x86/x64: PROCESSOR_ARCHITECTURE_INTEL, PROCESSOR_ARCHITECTURE_AMD64,
PROCESSOR_ARCHITECTURE_IA64, PROCESSOR_ARCHITECTURE_MIPS, PROCESSOR_ARCHITECTURE_ALPHA,
PROCESSOR_ARCHITECTURE_PPC, PROCESSOR_ARCHITECTURE_UNKNOWN
- GetProductInfo indicates: PRODUCT_BUSINESS, PRODUCT_BUSINESS_N, PRODUCT_CLUSTER_SERVER,
PRODUCT_DATACENTER_SERVER, PRODUCT_DATACENTER_SERVER_CORE, PRODUCT_DATACENTER_SERVER_CORE_V,
PRODUCT_DATACENTER_SERVER_V, PRODUCT_ENTERPRISE, PRODUCT_ENTERPRISE_N,
PRODUCT_ENTERPRISE_SERVER, PRODUCT_ENTERPRISE_SERVER_CORE, PRODUCT_ENTERPRISE_SERVER_CORE_V,
PRODUCT_ENTERPRISE_SERVER_IA64, PRODUCT_ENTERPRISE_SERVER_V, PRODUCT_HOME_BASIC,
PRODUCT_HOME_BASIC_N, PRODUCT_HOME_PREMIUM, PRODUCT_HOME_PREMIUM_N, PRODUCT_HOME_SERVER,
PRODUCT_HYPERV, PRODUCT_MEDIUMBUSINESS_SERVER_MANAGEMENT,
PRODUCT_MEDIUMBUSINESS_SERVER_MESSAGING, PRODUCT_MEDIUMBUSINESS_SERVER_SECURITY,
PRODUCT_SERVER_FOR_SMALLBUSINESS, PRODUCT_SERVER_FOR_SMALLBUSINESS_V,
PRODUCT_SMALLBUSINESS_SERVER, PRODUCT_STANDARD_SERVER, PRODUCT_STANDARD_SERVER_CORE,
PRODUCT_STANDARD_SERVER_CORE_V, PRODUCT_STANDARD_SERVER_V, PRODUCT_STARTER,
PRODUCT_STORAGE_ENTERPRISE_SERVER, PRODUCT_STORAGE_EXPRESS_SERVER,
PRODUCT_STORAGE_STANDARD_SERVER, PRODUCT_STORAGE_WORKGROUP_SERVER, PRODUCT_UNDEFINED,
PRODUCT_ULTIMATE, PRODUCT_ULTIMATE_N, PRODUCT_WEB_SERVER, PRODUCT_WEB_SERVER_CORE,
PRODUCT_UNLICENSED
- GetSystemMetrics indicates SM_MEDIACENTER, SM_STARTER, SM_TABLETPC, SM_SERVERR2
- OSVERSIONINFOEX.wProductType indicates VER_NT_WORKSTATION,VER_NT_SERVER,VER_NT_DOMAIN_CONTROLLER
- OSVERSIONINFOEX.wSuiteMask indicates bitmask: VER_SUITE_BACKOFFICE, VER_SUITE_BLADE,
VER_SUITE_COMPUTE_SERVER, VER_SUITE_DATACENTER, VER_SUITE_ENTERPRISE, VER_SUITE_EMBEDDEDNT,
VER_SUITE_PERSONAL, VER_SUITE_SINGLEUSERTS, VER_SUITE_SMALLBUSINESS,
VER_SUITE_SMALLBUSINESS_RESTRICTED, VER_SUITE_STORAGE_SERVER, VER_SUITE_TERMINAL,
VER_SUITE_WH_SERVER
Determine usable Vista version (64bit)
Version
Home Basic / Premium
Business
Enterprise
Ultimate
Max Memory
8GB/16GB
128GB
128GB
128GB
Remote desktop
No
Yes
Yes
Yes
Remote desktop is a must in order to reach you computer when not at home. There is no advantage of Enterprice/Ultimate on top of
Business, except perhaps for Virtual PC support, MediaCenter and MUA support (on-the-flight change of display language, which does not
realy change everything anyway). The N-versions are ofcourse in any way unusable.
So the best choice is Vista Business.
References
KB283037:
KB810371:
KB171793:
KB316739:
KB294418:
/3GB option
/USERVA option, exchange server
/3GB option
/USERVA option
Comparison of 32-bit and 64-bit memory architecture for 64-bit editions of Windows XP and Windows Server 2003
Inside SQL Server 2000's Memory Management Facilities
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnsqldev/html/sqldev_01262004.asp
The following references are included in this document:
PAE, WHDC: Memory Support and Windows Operating Systemss
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx
KB294418: Comparison of 32-bit and 64-bit memory architecture for 64-bit editions of Windows XP and Windows Server 2003
http://support.microsoft.com/kb/294418
3GB boot.ini option
http://msdn.microsoft.com/en-us/library/ms791558.aspx
BCDEdit Vista boot parameters tool
http://msdn.microsoft.com/en-us/library/aa906211.aspx
Memory Limits for Windows Releases
http://msdn.microsoft.com/en-us/library/aa366778.aspx
Windows Vista Starter Fact Sheet
http://www.microsoft.com/presspass/newsroom/windows/factsheets/WinVistaStarterFS.mspx
Vista versions
http://windowsitpro.com/article/articleid/47669/pre-pdc-exclusive-windows-vista-processor-and-memory-support-revealed.html
Windows Vista Product Editions
http://www.winsupersite.com/showcase/winvista_editions_final.asp
Operating Systems and PAE Support
http://www.microsoft.com/whdc/system/platform/server/PAE/pae_os.mspx
Memory Limits for Windows Releases
http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx
Memory Limits for Windows Releases
http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx
Memory Limits for Windows Releases
This topic describes memory limits for supported Windows releases:















Memory and Address Space Limits
Physical Memory Limits: Windows 7
Physical Memory Limits: Windows Server 2008 R2
Physical Memory Limits: Windows Server 2008
Physical Memory Limits: Windows Vista
Physical Memory Limits: Windows Home Server
Physical Memory Limits: Windows Server 2003 R2
Physical Memory Limits: Windows Server 2003 with Service Pack 2 (SP2)
Physical Memory Limits: Windows Server 2003 with Service Pack 1 (SP1)
Physical Memory Limits: Windows Server 2003
Physical Memory Limits: Windows XP
Physical Memory Limits: Windows 2000
Physical Memory Limits: Windows Embedded
How graphics cards and other devices affect memory limits
Related Topics
Limits on memory and address space vary by platform, operating system, and by whether the IMAGE_FILE_LARGE_ADDRESS_AWARE
value of the LOADED_IMAGE structure and 4-gigabyte tuning (4GT) are in use. IMAGE_FILE_LARGE_ADDRESS_AWARE is set or
cleared by using the /LARGEADDRESSAWARE linker option.
4-gigabyte tuning (4GT), also known as application memory tuning, or the /3GB switch, is a technology (only applicable to 32 bit systems)
that alters the amount of virtual address space available to user mode applications. Enabling this technology reduces the overall size of the
system virtual address space and therefore system resource maximums. For more information, see What is 4GT.
Limits on physical memory for 32-bit platforms also depend on the Physical Address Extension (PAE), which allows 32-bit Windows
systems to use more than 4 GB of physical memory.
1.1.1 Memory and Address Space Limits
The following table specifies the limits on memory and address space for supported releases of Windows. Unless otherwise noted, the
limits in this table apply to all supported releases.
Memory type
Limit in on X86
Limit in 64-bit Windows
User-mode
virtual
address
space for
each 32-bit
process
2 GB
Up to 3 GB with IMAGE_FILE_LARGE_ADDRESS_AWARE
and 4GT
2 GB with
IMAGE_FILE_LARGE_ADDRESS_AWARE
cleared (default)
4 GB with
IMAGE_FILE_LARGE_ADDRESS_AWARE set
User-mode
virtual
address
space for
each 64-bit
process
Not applicable
With IMAGE_FILE_LARGE_ADDRESS_AWARE
set (default):
x64: 8 TB
Intel IPF: 7 TB
2 GB with
IMAGE_FILE_LARGE_ADDRESS_AWARE
cleared
Kernel-mode
virtual
address
space
2 GB
From 1 GB to a maximum of 2 GB with 4GT
8 TB
Paged pool
Limited by available kernel-mode virtual address space or the
PagedPoolLimit registry key value.
Windows Vista and above: Limited only by kernel mode virtual
address space. Starting with Windows Vista with Service Pack 1
(SP1), the paged pool can also be limited by the PagedPoolLimit
registry key value.
Windows Home Server and Windows Server 2003: 530 MB
Windows XP: 490 MB
Windows 2000: 350 MB
128 GB
Windows Server 2003 and Windows XP: Up to
128 GB depending on configuration and RAM.
Windows
PAE: Memory Support and Windows Operating Systemss
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx
Memory Support and Windows Operating Systems
Updated: February 9, 2005
Operating systems based on Microsoft Windows NT technologies have always provided applications with a flat 32-bit virtual address space
that describes 4 gigabytes (GB) of virtual memory. The address space is usually split so that 2 GB of address space is directly accessible to
the application and the other 2 GB is only accessible to the Windows executive software.
The 32-bit versions of the Windows 2000 Advanced Server and Windows NT Server 4.0, Enterprise Edition, operating systems were the
first versions of Windows to provide applications with a 3-GB flat virtual address space, with the kernel and executive components using
only 1 GB. In response to customer requests, Microsoft has expanded the availability of this support to the 32-bit version of Windows XP
Professional and all 32-bit versions of Windows Server 2003.
Windows 2000 Memory Support. With Windows 2000 Professional and Server, the maximum amount of memory that can be supported is
4 GB (identical to Windows NT 4.0, as described later in this section). However, Windows 2000 Advanced Server supports 8 GB of physical
RAM and Windows 2000 Datacenter Server supports 32 GB of physical RAM using the PAE feature of the IA-32 processor family,
beginning with Intel Pentium Pro and later.
Windows XP Professional and Windows Server 2003 Memory Support. The maximum amount of memory that can be supported on
Windows XP Professional and Windows Server 2003 is also 4 GB. However, Windows Server 2003, Enterprise Edition supports 32 GB of
physical RAM and Windows Server 2003, Datacenter Edition supports 64 GB of physical RAM using the PAE feature.
The virtual address space of processes and applications is still limited to 2 GB unless the /3GB switch is used in the Boot.ini file. When the
physical RAM in the system exceeds 16 GB and the /3GB switch is used, the operating system will ignore the additional RAM until the /3GB
switch is removed. This is because of the increased size of the kernel required to support more Page Table Entries. The assumption is
made that the administrator would rather not lose the /3GB functionality silently and automatically; therefore, this requires the administrator
to explicitly change this setting.
The /3GB switch allocates 3 GB of virtual address space to an application that uses IMAGE_FILE_LARGE_ADDRESS_AWARE in the
process header. This switch allows applications to address 1 GB of additional virtual address space above 2 GB.
The virtual address space of processes and applications is still limited to 2 GB, unless the /3GB switch is used in the Boot.ini file. The
following example shows how to add the /3GB parameter in the Boot.ini file to enable application memory tuning:
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(2)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(2)\WINNT="????" /3GB
Note: "????" in the previous example can be the programmatic name of any of the following operating system versions:
Windows XP Professional
Windows Server 2003
Windows Server 2003, Enterprise Edition
Windows Server 2003, Datacenter Edition
Windows 2000 Advanced Server
Windows 2000 Datacenter Server
Windows NT Server 4.0, Enterprise Edition
Windows NT 4.0 Memory Support. With Microsoft Windows NT 4.0 Workstation and Server operating systems, the maximum amount of
physical memory supported is 4 GB. The maximum amount of virtual memory is 2 GB.
With Windows NT 4.0 Server, Enterprise Edition, the /3GB switch was first added to Boot.ini.
Application Memory Tuning. This capability allows memory-intensive applications to utilize up to 50 percent more virtual memory on Intelbased computers. Application memory tuning provides more of the computer's virtual memory to applications by providing less virtual
memory to the operating system.
Application Changes. No APIs are required to support application memory tuning. However, it would be ineffective to automatically
provide every application with a 3-GB address space.
Executables that can use the 3-GB address space are required to have the bit IMAGE_FILE_LARGE_ADDRESS_AWARE set in their
image header. If you are the developer of the executable, you can specify a linker flag (/LARGEADDRESSAWARE).
To set this bit, you must use Microsoft Visual Studio Version 6.0 or later and the Editbin.exe utility, which has the ability to modify the image
header (/LARGEADDRESSAWARE) flag. For more information on setting this flag, see the Microsoft Visual Studio documentation.
Some manufacturers preconfigure their applications to use application memory tuning, making it unnecessary for you to make this change.
For more information, see your application documentation and contact your application vendor to determine whether they support Large
Address Awareness or whether you can enable it in their application.
Physical Address Extension. PAE is an Intel-provided memory address extension that enables support of up to 64 GB of physical
memory for applications running on most 32-bit (IA-32) Intel Pentium Pro and later platforms. Support for PAE is provided under Windows
2000 and 32-bit versions of Windows XP and Windows Server 2003. 64-bit versions of Windows do not support PAE.
PAE allows the most recent IA-32 processors to expand the number of bits that can be used to address physical memory from 32 bits to 36
bits through support in the host operating system for applications using the Address Windowing Extensions (AWE) application programming
interface (API). More information about the AWE API can be found at the MSDN Library.
KB294418: Comparison of 32-bit and 64-bit memory architecture for 64-bit editions of Windows XP and Windows Server 2003
http://support.microsoft.com/kb/294418
MORE INFORMATION
Virtual memory
This is a method of extending the available physical memory on a computer.
In a virtual memory system, the operating system creates a pagefile, or swapfile, and divides memory into units called pages. Recently
referenced pages are located in physical memory, or RAM.
If a page of memory is not referenced for a while, it is written to the pagefile. This is called "swapping" or "paging out" memory. If that piece
of memory is then later referenced by a program, the operating system reads the memory page back from the pagefile into physical
memory, also called "swapping" or "paging in" memory.
The total amount of memory that is available to programs is the amount of physical memory in the computer in addition to the size of the
pagefile. An important consideration in the short term is that even 32-bit applications will benefit from increased virtual memory address
space when they are running in Windows x64 Editions.
Applications that are compiled with the /LARGEADDRESSAWARE option, as would be required to take advantage of the /3GB switch in
32-bit Windows, will automatically be able to address 4 GB of virtual memory without any boot time switches or changes to x64 Windows.
Plus, of course, the operating system does not have to share that 4 GB of space. Therefore, it is not constrained at all.
Back to the top
Paging file
This is a disk file that the computer uses to increase the amount of physical storage for virtual memory.
Back to the top
Hyperspace
This is a special region that is used to map the process working set list and to temporarily map other physical pages for such operations as
zeroing a page on the free list (when the zero list is empty and the zero page is needed), invalidating page table entries in other page tables
(such as when a page is removed from the standby list), and in regards to process creation, setting up the address space of a new process.
Back to the top
Paged pool
This is a region of virtual memory in system space that can be paged in and out of the working set of the system process. Paged pool is
created during system initialization and is used by Kernel-mode components to allocate system memory. Uniproccessor systems have two
paged pools, and multiprocessor systems have four. Having more than one paged pool reduces the frequency of system code blocking on
simultaneous calls to pool routines.
Back to the top
Non-paged pool
This is a memory pool that consists of ranges of system virtual addresses that are guaranteed to be resident in physical memory at all times
and thus can be accessed from any address space without incurring paging input/output (I/O). Non-paged pool is created during system
initialization and is used by Kernel-mode components to allocate system memory.
Back to the top
System cache
These are pages that are used to map open files in the system cache.
Back to the top
System PTEs
A pool of system Page Table Entries (PTEs) that is used to map system pages such as I/O space, Kernel stacks, and memory descriptor
lists. 64-bit programs use a 16-terabyte tuning model (8 terabytes User and 8 terabytes Kernel). 32-bit programs still use the 4-GB tuning
model (2 GB User and 2 GB Kernel). This means that 32-bit processes that run on 64-bit versions of Windows run in a 4-GB tuning model
(2 GB User and 2GB Kernel). 64-bit versions of Windows do not support the use of the /3GB switch in the boot options. Theoretically, a 64bit pointer could address up to 16 exabytes. 64-bit versions of Windows have currently implemented up to 16 terabytes of address space.
3GB boot.ini option
http://msdn.microsoft.com/en-us/library/ms791558.aspx
/3GB
On 32-bit versions of Windows, the /3GB parameter enables 4 GT RAM Tuning, a feature that enlarges the user-mode virtual address
space to 3 GB and restricts the kernel-mode components to the remaining 1 GB.
/3GB [ /userva=SizeInMB ]
1.1.1.1
Subparameters
/userva
Specifies an alternate amount of user-mode virtual address space for operating systems booted with the /3GB parameter.
SizeInMB
Specifies the amount of memory, in megabytes, for user-mode virtual address space. This variable can have any value between
2048 (2 GB) and 3072 (3 GB) megabytes in decimal notation. Windows uses the remaining address space (4 GB minus the
specified amount) as its kernel-mode address space.
1.1.1.2
Comments
The /3GB parameter is supported on Windows Server 2003, Windows XP, Windows 2000, and Windows NT. On Windows Vista and later
versions of Windows, use the IncreaseUserVA element in BCDEdit.
On Windows, by default, the lower 2 GB are reserved for user-mode programs and the upper 2 GB are reserved for kernel-mode programs.
You can use this parameter to test the performance of your driver when it is running in a 1 GB kernel.
The 4 GT RAM Tuning feature is fully functional on Microsoft Windows NT Server 4.0, Enterprise Edition with Service Pack 3, Microsoft
Windows 2000 Advanced Server, Microsoft Windows 2000 Datacenter Server, and all editions of Windows XP, Windows Server 2003,
Windows Vista, and later versions of Windows.
On other versions of Windows NT and Windows 2000, this feature restricts the kernel to addresses above the 3 GB boundary. However,
user-mode applications cannot access more than 2 GB of address space.
The /userva subparameter is designed for computers that need more than 2 GB but less than 3 GB of user-mode address space,
particularly those that are running memory-intensive user-mode programs. When used without the /3GB parameter, /userva is ignored.
The /3GB and /userva parameters are valid only on boot entries for 32-bit versions of Windows on computers with x86 or x64-based
processors.
To take advantage of the 3 GB available to user-mode programs, the program must be linked with the /LARGEADDRESSAWARE option.
On 64-bit versions of Windows Server 2003, the system automatically expands the virtual address space available to 32-bit user-mode
programs linked with the /LARGEADDRESSAWARE option as needed without the /3GB boot parameter. On Windows Server 2003 RTM
(without Service Pack 1), these 32-bit programs can access up to 3 GB of virtual address space. On Windows Server 2003 with Service
Pack 1, they can access up to 4 GB of virtual address space. Native 64-bit user-mode programs can access up to 8 TB of virtual address
space.
Booting with the /3GB parameter decreases the amount of kernel virtual address space on the system. In order to fit all of the kernel
resources within the remaining 1 GB of virtual memory, NT-based Windows operating systems prior to Windows Vista, Windows restricts
physical memory to frames below the 16 GB physical boundary and on Windows Vista, it restricts physical memory to frames below the
64 GB boundary. Because allocation of memory resources in Windows Vista is dynamic and, therefore, more adaptable and efficient, the
system can devote more memory space to addressing, thereby accommodating more physical memory.
The following table lists the physical memory limits of 32-bit Windows operating systems that support the use of more than 4 GB of physical
memory with and without the /3GB boot parameter.
Operating system
Physical memory limit without /3GB
Physical memory limit with /3GB
Windows Vista
4 GB
4 GB (no effect)
Windows Vista, Datacenter Edition
128 GB
64 GB
Windows Server 2003, Enterprise Edition
32 GB
16 GB
Windows Server 2003, Enterprise Edition SP1
64 GB
16 GB
Windows Server 2003, Datacenter Edition
128 GB
16 GB
Windows Server 2003, Datacenter Edition SP1
128 GB
16 GB
Windows XP (all editions)
4 GB
4 GB (no effect)
On Windows XP, some drivers, especially video adapter drivers with onboard RAM, cannot run with the /3GB parameter because they
require more address space than the 1 GB kernel address space permits.
1.1.1.3
Examples
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003, Enterprise" /fastdetect /3GB
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003, Enterprise" /fastdetect /3GB /userva=3030
1.1.1.4
Bootcfg Commands
bootcfg /raw "/3GB" /A /ID 1
bootcfg /raw "/3GB /userva=3030" /A /ID 2
BCDEdit Vista boot parameters tool
http://msdn.microsoft.com/en-us/library/aa906211.aspx
BCDEdit /set
The /set command sets a boot entry option value in the boot configuration data store. Use this command to configure specific boot entry
elements, such as kernel debugger settings, data execution protection (DEP) and processor address extension (PAE) options, and to load
alternate hardware abstraction layer (HAL) and kernel files.
bcdedit /set [{ID}] datatype value
1.1.1.5
Parameters
[{ID}
The {ID} is the GUID that is associated with the boot entry. If you do not specify an {ID}, the command modifies the current
operating system boot entry. If a boot entry is specified, the GUID associated with the boot entry must be enclosed in braces { }.
To view the GUID identifiers for all of the active boot entries, use the bcdedit /enum command.
1.1.1.6
datatype value
bootlog [ yes | no]
Enables the system initialization log.
hal file
Directs the operating system loader to load an alternate HAL file. The specified file must be located in the
%SystemRoot%\system32 directory, and its file name must conform to 8.3−character format.
increaseuserva Megabytes
Specifies the amount of memory, in megabytes, for user-mode virtual address space. This variable can have any value between
2048 (2 GB) and 3072 (3 GB) megabytes in decimal notation. Windows uses the remaining address space (4 GB minus the
specified amount) as its kernel-mode address space.
kernel file
Directs the operating system loader to load an alternate kernel. The specified file must be located in the
%SystemRoot%\system32 directory, and its file name must conform to 8.3−character format.
loadoptions /busparams=Bus.Device.Function
Specifies the target controller when multiple controllers exist. This syntax is appropriate when using either a 1394 cable or a
USB 2.0 debug cable for debugging. Bus specifies the bus number, Device specifies the device number, and Function specifies
the function number. For USB 2.0 debugging ,the bus parameters must be specified in hexadecimal. For 1394 debugging, the
bus parameters must be specified in decimal.
nolowmem [ on | off ]
Controls the use of low memory. When nolowmem on is specified, this option loads the operating system, device drivers, and
all applications into addresses above the 4 GB boundary, and directs Windows to allocate all memory pools at addresses above
the 4 GB boundary.
nx [Optin |OptOut | AlwaysOn |AlwaysOff]
Enables, disables, and configures Data Execution Prevention (DEP), a set of hardware and software technologies designed to
prevent harmful code from running in protected memory locations. For information about how to use the Control Panel to
change the DEP settings, see the
Change Data Execution Prevention settings page on the Windows Help and How-to Web
site.
Optin
Enables DEP only for operating system components, including the Windows kernel and drivers. Administrators can enable DEP
on selected executable files by using the Application Compatibility Toolkit (ACT).
Optout
Enables DEP for the operating system and all processes, including the Windows kernel and drivers. However, administrators
can disable DEP on selected executable files by using System in Control Panel.
AlwaysOn
Enables DEP for the operating system and all processes, including the Windows kernel and drivers. All attempts to disable DEP
are ignored.
AlwaysOff
Disables DEP. Attempts to enable DEP selectively are ignored.
On Windows Vista, this parameter also disables Physical Address Extension (PAE). This parameter does not disable PAE on
Windows Server 2008.
onecpu [ on | off ]
Forces only the boot CPU to be used in a computer that has more than one logical processor.
For example, the following command configures the current operating system loader to use one processor.
bcdedit /set onecpu on
pae [ Default | ForceEnable | ForceDisable ]
The pae parameter is valid only on boot entries for 32-bit versions of Windows that run on computers with x86-based and x64based processors. On 32-bit versions of Windows, PAE is disabled by default. However, Windows automatically enables PAE
when the computer is configured for hot-add memory devices in memory ranges beyond the 4 GB region, as defined by the
Static Resource Affinity Table (SRAT). Hot-add memory supports memory devices that you can add without rebooting or turning
off the computer. In this case, because PAE must be enabled when the system starts, it is enabled automatically so that the
system can immediately address extended memory that is added between restarts. Hot-add memory is supported only on
Windows Server 2008, Enterprise Edition, Windows Server 2003, Enterprise Edition and Windows Server 2003, Datacenter
Edition, and only on computers with an ACPI BIOS, an x86-based processor, and specialized hardware.
On a computer that supports hardware-enabled Data Execution Prevention (DEP) and is running a 32-bit version of the
Windows operating system that supports DEP, PAE is automatically enabled when DEP is enabled and, on all 32-bit versions of
the Windows operating system, except Windows Server 2003 with SP1, PAE is disabled when you disable DEP. To enable
PAE when DEP is disabled, you must enable PAE explicitly, by using /set nx AlwaysOff and /set pae ForceEnable. For more
information about DEP, see Boot Parameters to Configure DEP and PAE
PAE is required to support Cache Coherent Non-Uniform Memory Architecture (known as ccNUMA or NUMA) on computers
with x86 processors, although Windows can run in non-NUMA mode on NUMA-capable computers without PAE. Even when it
is required, PAE is not enabled automatically. NUMA is supported in all editions of Windows XP and Windows Vista, and in the
Enterprise and Datacenter editions of Windows Server 2003.
For more information about using the pae parameter and the other parameters that affect PAE configuration, see Boot
Parameters to Configure DEP and PAE.
If you are running a 32-bit version of Windows Vista on a computer that has 4 GB of memory installed, the amount of RAM
available for use could be less than what you would expect. For more information about memory usage, see article Q929605,
"The system memory that is reported in the System Information dialog box in Windows Vista is less than you expect if 4 GB
of RAM is installed" in the Microsoft Knowledge Base.
quietboot [ on | off ]
Controls the display of a high-resolution bitmap in place of the Windows boot screen display and animation. In operating
systems prior to Windows Vista, the /noguiboot serves a similar function.
removememory Megabytes
Removes memory from the total available memory that the operating system can use.
For example, the following command removes 256 MB of memory from the total available to the operating system associated
with the specified boot entry.
bcdedit /set {49916baf-0e08-11db-9af4-000bdbd316a0} removememory 256
sos [ on | off ]
Controls the display of the names of the drivers as they load during the boot process. Use sos on to display the names. Use
sos off to suppress the display.
truncatememory address
Limits the amount of physical memory available to Windows. When you use this option, Windows ignores all memory at or
above the specified physical address. Specify the address in bytes.
For example, the following command sets the physical address limit at 1 GB. You can specify the address in decimal
(1073741824) or hexadecimal (0x40000000).
bcdedit /set {49916baf-0e08-11db-9af4-000bdbd316a0} truncatememory Ox40000000
usefirmwarepcisettings [ yes | no ]
Enables or disables the use of BIOS-configured peripheral component interconnect (PCI) resources.
vga [ on | off ]
Forces the use of the VGA display driver.
1.1.1.7
Comment
For more information about specific BCD elements and boot options, you can use the commands BCDEdit /? OSLOADER and BCDEdit
/? TYPES OSLOADER.
To view the current boot entries and their settings, use the bcdedit /enum command. This command displays the active boot entries and
their associated globally unique identifiers (GUID). Use the identifiers with the /set command to configure options for a specific boot entry.
For information about commonly used BCDEdit commands, see
Boot Configuration Data Editor Frequently Asked Questions
Memory Limits for Windows Releases
http://msdn.microsoft.com/en-us/library/aa366778.aspx
Memory Limits for Windows Releases
This topic describes memory limits for supported Windows releases:







Memory and Address Space Limits
Physical Memory Limits: Windows Server 2008
Physical Memory Limits: Windows Vista
Physical Memory Limits: Windows Home Server
Physical Memory Limits: Windows Server 2003
Physical Memory Limits: Windows XP
Physical Memory Limits: Windows 2000
Limits on memory and address space vary by platform, operating system, and by whether the IMAGE_FILE_LARGE_ADDRESS_AWARE
value of the LOADED_IMAGE structure and 4-gigabyte tuning (4GT) are in use.
Limits on physical memory for 32-bit platforms also depend on the Physical Address Extension (PAE), which allows 32-bit Windows
systems to use more than 4 GB of physical memory.
1.1.2 Memory and Address Space Limits
The following table specifies the limits on memory and address space for supported releases of Windows.
Memory type
Limit in 32-bit Windows
Limit in 64-bit Windows
User-mode virtual
address space
for each 32-bit
process
2 GB
Up to 3 GB with IMAGE_FILE_LARGE_ADDRESS_AWARE
and 4GT
2 GB
4 GB with
IMAGE_FILE_LARGE_ADDRESS_AWARE
User-mode virtual
address space
for each 64-bit
process
Not applicable
2 GB
x64: 8 TB with
IMAGE_FILE_LARGE_ADDRESS_AWARE
Intel IPF: 7 TB with
IMAGE_FILE_LARGE_ADDRESS_AWARE
Kernel-mode
virtual address
space
2 GB
From 1 GB to a maximum of 2 GB with 4GT
8 TB
Paged pool
Limited by available kernel-mode virtual address space or
the PagedPoolLimit registry key value.
Windows Vista: Limited only by kernel mode virtual
address space. Starting with Windows Vista Service Pack 1
(SP1), the paged pool can also be limited by the
PagedPoolLimit registry key value.
Windows Home Server and Windows Server 2003: 530
MB
Windows XP: 490 MB
Windows 2000: 350 MB
128 GB
Windows Server 2003 and Windows XP: Up
to 128 GB depending on configuration and RAM.
Windows 2000: Not applicable
Nonpaged pool
Limited by available kernel-mode virtual address space, the
NonPagedPoolLimit registry key value, or physical memory.
Windows Vista: Limited only by kernel mode virtual
address space and physical memory. Starting with
Windows Vista SP1, the nonpaged pool can also be limited
by the NonPagedPoolLimit registry key value.
Windows Home Server, Windows Server 2003, and
Windows XP/2000: 256 MB, or 128 MB with 4GT.
75% of RAM up to a maximum of 128 GB
Windows Vista: 40% of RAM up to a maximum
of 128 GB.
Windows Server 2003 and Windows XP: Up
to 128 GB depending on configuration and RAM.
Windows 2000: Not applicable
System cache
virtual address
space (physical
size limited only
by physical
memory)
Limited by available kernel-mode virtual address space or
the SystemCacheLimit registry key value.
Windows Vista: Limited only by kernel mode virtual
address space. Starting with Windows Vista SP1, system
cache virtual address space can also be limited by the
SystemCacheLimit registry key value.
Windows Home Server, Windows Server 2003, and
Windows XP/2000: 860 MB with LargeSystemCache
registry key set and without 4GT; up to 448 MB with 4GT.
Always 1 TB regardless of physical RAM
Windows Server 2003 and Windows XP: Up
to 1 TB depending on configuration and RAM.
Windows 2000: Not applicable
1.1.3 Physical Memory Limits: Windows Server 2008
The following table specifies the limits on physical memory for Windows Server 2008. Limits greater than 4 GB for 32-bit Windows assume
that PAE is enabled.
Version
Limit in 32-bit Windows
Limit in 64-bit Windows
Windows Server 2008 Datacenter (full installation)
64 GB
2 TB
Windows Server 2008 Datacenter (Server Core installation)
64 GB
2 TB
Windows Server 2008 Enterprise
64 GB
2 TB
Windows Server 2008 Standard
4 GB
32 GB
Windows Server 2008 for Itanium-Based Systems
Not applicable
2 TB
Windows Web Server 2008
4 GB
32 GB
1.1.4 Physical Memory Limits: Windows Vista
The following table specifies the limits on physical memory for Windows Vista.
Version
Limit in 32-bit Windows
Limit in 64-bit Windows
Windows Vista Ultimate
4 GB
128 GB
Windows Vista Enterprise
4 GB
128 GB
Windows Vista Business
4 GB
128 GB
Windows Vista Home Premium
4 GB
16 GB
Windows Vista Home Basic
4 GB
8 GB
Windows Vista Starter
4 GB
Not applicable
1.1.5 Physical Memory Limits: Windows Home Server
Windows Home Server is available only in a 32-bit edition. The physical memory limit is 4 GB.
1.1.6 Physical Memory Limits: Windows Server 2003
The following table specifies the limits on physical memory for Windows Server 2003. Limits over 4 GB for 32-bit Windows assume that
PAE is enabled.
Version
Limit in 32-bit Windows
Limit in 64-bit Windows
Windows Server 2003 Service Pack 2 (SP2), Datacenter Edition
128 GB
64 GB with 4GT
2 TB
Windows Server 2003 Service Pack 2 (SP2), Enterprise Edition
64 GB
2 TB
Windows Storage Server 2003, Enterprise Edition
8 GB
Not applicable
Windows Storage Server 2003
4 GB
Not applicable
Windows Server 2003 R2 Datacenter Edition
Windows Server 2003 with Service Pack 1 (SP1), Datacenter Edition
128 GB
16 GB with 4GT
1 TB
Windows Server 2003 R2 Enterprise Edition
Windows Server 2003 with Service Pack 1 (SP1), Enterprise Edition
64 GB
16 GB with 4GT
1 TB
Windows Server 2003 R2 Standard Edition
Windows Server 2003, Standard Edition SP1
Windows Server 2003, Standard Edition SP2
4 GB
32 GB
Windows Server 2003, Datacenter Edition
128 GB
16 GB with 4GT
512 GB
Windows Server 2003, Enterprise Edition
32 GB
16 GB with 4GT
64 GB
Windows Server 2003, Standard Edition
4 GB
16 GB
Windows Server 2003, Web Edition
2 GB
Not applicable
Windows Small Business Server 2003
4 GB
Not applicable
Windows Compute Cluster Server 2003
Not applicable
32 GB
1.1.7 Physical Memory Limits: Windows XP
The following table specifies the limits on physical memory for Windows XP.
Version
Limit in 32-bit Windows
Limit in 64-bit Windows
Windows XP
4 GB
128 GB
Windows XP Starter Edition
512 MB
Not applicable
1.1.8 Physical Memory Limits: Windows 2000
The following table specifies the limits on physical memory for Windows 2000.
Version
Limit in 32-bit Windows
Windows 2000 Professional
4 GB
Windows 2000 Server
4 GB
Windows 2000 Advanced Server
8 GB
Windows 2000 Datacenter Server
32 GB
Architectural component
64-bit Windows
32-bit Windows
Virtual memory
16 terabytes
4 GB
Paging file size
256 terabytes
16 terabytes
Hyperspace
8 GB
4 MB
Paged pool
128 GB
470 MB
Non-paged pool
128 GB
256 MB
System cache
1 terabyte
1 GB
System PTEs
128 GB
660 MB
Operating Systems and PAE Support
http://www.microsoft.com/whdc/system/platform/server/PAE/pae_os.mspx
Operating Systems and PAE Support
Updated: July 14, 2006
1.1.8.1.2
On This Page
1.1.8.1.1
Related Links
PAE: 32- vs. 64-Bit Systems
• PAE Memory and Windows
Technical Background
Operating System Implementation and Application Support
Technical Issues with Large Memory Support in IA32
Windows and PAE
1.2 PAE: 32- vs. 64-Bit Systems
Addressing physical memory above 4 GB requires more than the 32 bits of address offered by the standard operating mode of Intel (32-bit)
processors. To this end, Intel introduced the 36-bit physical addressing mode called PAE, starting with the Intel Pentium Pro processor.
This article describes some techniques that Microsoft Windows operating systems and several UNIX operating systems use to provide
support to applications using PAE mode addressing. Because processes running in these environments have 32-bit pointers, the operating
system must manage and present PAE's 36 bits of address in such a way that the applications can practically use it. The key question is:
how does the operating system solve this problem? The performance, functionality, simplicity of programming, and reliability of how these
issues are handled will determine the usefulness of the large memory support.
PAE is supported only on 32-bit versions of the Windows operating system; 64-bit versions of Windows do not support PAE. For
information about device driver and system requirements for 64-bit versions of Windows, see 64-bit System Design. The Address
Windowing Extension (AWE) API is supported on 32-bit systems. It is also supported on x64 systems for both native and Wow64
applications.
Although support for PAE memory is typically associated with support for more than 4 GB of RAM, PAE can be enabled on Windows XP
SP2, Windows Server 2003, and later 32-bit versions of Windows to support hardware-enforced Data Execution Prevention (DEP).
The information in this article applies to Windows 2000, Windows XP Professional, Windows Server 2003, and later versions of these
operating systems, referred to as "Windows" in this paper.
Top of page
1.3 Technical Background
Address Translation in standard 32-bit mode
All IA-32 processors (Intel Pentium, Pentium Pro, Pentium II Xeon, and Pentium III Xeon) support 32 bits of physical address (4 GB),
allowing applications to address 4 GB of virtual address when they are running. The system must translate the 32-bit virtual address that
the applications and operating system use to the 32-bit physical address used by the hardware. (Pentium Pro was the first processor in the
IA-32 family to support PAE, but chipset support is also required for 36-bit physical addresses, which was usually lacking.)
Windows uses two levels of mapping to do the translation, which is facilitated by a set of data structures called page directories and page
tables that the memory manager creates and maintains.
PSE Mode
IA-32 supports two methods to access memory above 4 GB (32 bits). PSE (Page Size Extension) was the first method, which shipped with
the Pentium II. This method offers a compatibility advantage because it kept the PTE (page table entry) size of 4 bytes. However, the only
practical implementation of this is through a driver. This approach suffers from significant performance limitations, due to a buffer copy
operation necessary for reading and writing above 4 GB. PSE mode is used in the PSE 36 RAM disk usage model.
PSE uses a standard 1K directory and no page tables to extend the page size 4-MB (eliminating one level of indirection for that mode). The
Page Directory Entries (PDE) contains 14 bits of address, and when combined with the 22-bit byte index, yields the 36 bits of extended
physical address. Both 4-KB and 4-MB pages are simultaneously supported below 4 GB, with the 4-KB pages supported in the standard
way.
Note that pages located above 4 GB must use PSE mode (with 4-MB page sizes).
PAE Mode
PAE is the second method supported to access memory above 4 GB; this method has been widely implemented. PAE maps up to 64 GB of
physical memory into a 32-bit (4 GB) virtual address space using either 4-KB or 2-MB pages. The Page directories and the page tables are
extended to 8 byte formats, allowing the extension of the base addresses of page tables and page frames to 24 bits (from 20 bits). This is
where the extra four bits are introduced to complete the 36-bit physical address.
Windows supports PAE with 4-KB pages. PAE also supports a mode where 2-MB pages are supported. Many of the UNIX operating
systems rely on the 2 MB-page mode. The address translation is done without the use of page tables (the PDE supplies the page frame
address directly).
Top of page
1.4 Operating System Implementation and Application Support
The next issue is how the operating system can manage and present PAE's 36 bits of address in such a way that an application (with 32-bit
pointers) can practically use the additional memory.
There are five application support models. The first two models (Server Consolidation and Large Cache) are completely handled within the
operating system and require no changes to the application. The second two models (Application Windowing and Process Fork) require
application changes to support API extensions for large memory. The last model (PSE 36 RAM Disk) requires no changes to the operating
system (implemented in a driver), but mandates application changes to support the driver.
1. Server Consolidation
A PAE-enabled operating system should be capable of utilizing all physical memory provided by the system to load multiple applications;
for example, App#1, App#2, App #N, each consisting of 4 GB (maximum) of virtual address. In a non-PAE enabled system, the result can
be a great deal of paging, since maximum physical memory in the system is limited to 4 GB.
With the additional physical memory supported under PAE mode, an operating system can keep more of these applications in memory
without paging. This is valuable in supporting server consolidation configurations, where support of multiple applications in a single server is
typically required. Note that no application changes are required to support this capability.
2. Large Cache
Using additional PAE-enabled memory for a data cache is also possible. If the operating system supports this feature, applications need not
be recoded to take advantage of it. Windows Advanced Server and Datacenter Server support caching on a PAE platform and can utilize all
of the available memory.
3. Application Windowing
A PAE-enabled operating system can introduce an API to allow a properly coded application access to physical memory anywhere in the
system, even though it may be above 4 GB. Ideally, the API to allocate "high" physical memory and create or move the window should be
quick and simple to code. This is highly advantageous for applications that require fast access to large amounts of data in memory.
Sharing high memory between processes can introduce quite a bit of complexity into the API and the implementation. Windows avoids this
kind of sharing.
In addition, the support of paging makes the design and implementation of the operating system much more difficult and makes
deterministic performance more difficult to achieve. Windows avoids paging of high memory as well.
4. Process Fork and Shared Memory
This application support model splits the current process into two or more nearly identical copies. A copy is made of the user and system
stacks, the allocated data space, and the registers. The major difference is that one has the Process ID (PID) of the parent; the other has a
new PID. The fork returns a value that is a PID. The PID is zero for the copy that is the child or for the PID of the child for the copy that is
the parent.
5. PSE36 RAM Disk
Through use of a kernel device driver, much like a RAM disk, it is possible to utilize memory above 4 GB with no change whatsoever to the
operating system. Compatibility between the base operating system (running in 32-bit mode) and the driver (running in PAE mode) is
maintained since the page tables are kept at 4 bytes wide. The trade-offs for this very low development impact are several:
•
•
•
Performance degrades due to all I/O being forced to perform double buffering.
Application development impact is not appreciably less than that required for current APIs.
It cannot be used as a "consolidation server" because all applications share the same 4 GB physical memory space.
Design Implementation
The operating system implementations for large memory support must directly address these issues in order to be successful. The
simplicity, reliability, and performance of the operating system will be directly impacted, based on the design choices made in handling
these issues.
Top of page
1.5 Technical Issues with Large Memory Support in IA32
Memory Sharing and Inter-Process Communications
In all cases where memory remap is being used for allocating memory to processes, which is common to many PAE variants, memory
sharing is problematic. The physical memory being remapped is "outside" the process virtual address space. Thus, the physical memory is
less connected to the process in the sense of sharing the process's internal access and security controls, as well as those provided by the
operating system.
To apply access and security controls, it is necessary to greatly increase the bookkeeping required of the operating system memory
manager as well as the API set the application developer must use. This negatively impacts the high performance possible using very fast
remap operations. It is also important to remember that IPC/memory sharing may still take place between two processes' virtual address
spaces in any case, regardless of the physically mapped memory each may be using.
TLB Shoot-down
Translation Look-aside Buffers (TLBs) are processor registers, or a cache, that provides a direct logical-to-physical mapping of page table
entries. Once loaded, the processor has to read the page directories very infrequently (TLB misses) unless a task switch occurs.
During a remap operation, it is necessary to ensure that all processors have valid logical-to-physical mapping on chip. Therefore, remap
operations require a TLB shoot-down, because the logical-to-physical association is invalidated by the remap (where "logical" = the
application/process view of memory).
There is a performance impact while the processor (or processors) reload the TLB. All operating systems have this issue, and in the case of
PAE memory support, they ameliorate the issue in different ways:
•
•
Windows provides the ability for a single application to "batch" the remap operations required so that all happen simultaneously and only
cause one TLB shoot-down and one performance dip instead of random remaps, each of which would impact performance. This is quite
adequate for large applications, which are typically running on single-purpose systems.
Other operating systems provide "victim" buffers or allow one process to share another process's mappings, but at a cost of more
synchronization and API complexity.
Windows XP also provides this "batch" or Scatter/Gather functionality. Additionally, performance of these operations has been improved
for Windows Server 2003, Enterprise Edition and Datacenter Edition.
I/O
At one level or another, all the PAE variants support both 32-bit and 64-bit DMA I/O devices with the attendant drivers. However, there are
a number of provisos and conditions.
Kernel and memory organization
Typically, kernel memory space organization is unchanged from the standard kernel for the operating system. In many cases, items such
as the memory pool size remain the same. For backward compatibility, PCI base address registers (BARs) remain the same. Larger
memory sizes cause some shifting of kernel address space, usually when between 16 GB and 32 GB of memory is physically present in the
system.
One difference between operating systems is whether memory allocations are dynamic:
•
•
Some operating systems require the administrator to configure the amount of memory used for various purposes (caching, mapping,
consolidation, and so on).
Windows does not require the administrator to configure memory allocations, because the usage is dynamic, within the constraints of the
APIs used.
Hardware Support
The PCI standard provides a method whereby adapters may physically address more than 4 GB of memory by sending the high 32 bits of
address and the low 32 bits of address in two separate sends. This is called Dual Address Cycle (DAC) and is used both for 32-bit adapters
that understand 64-bit addresses but have only 32 address lines and for adapters that do have 64 address lines. This is a backward
compatibility feature.
Given the method with which PCI addresses memory beyond 32 bits, there is a failure mode that is subtle. Any I/O range that "spans"
across two 4-GB regions must be treated specially. If not, the address range will be correctly decoded for only one part of the transfer and
the remaining part will be transposed to an incorrect memory location. This will corrupt memory and will crash the system, crash the
application, or silently corrupt data at that location. Applications cannot prevent this because they are only presented virtual addresses and
have no visibility to the physical level. All operating systems that use PAE face this problem, but some do not explicitly prevent this from
occurring and instead depend on the device driver to take the correct actions.
Windows, however, explicitly prevents this problem. When an I/O range spans in this fashion, Windows returns two separate addresses
and ranges to the device and driver. The final special case is the first transition from 4 GB to beyond. No DAC is required for the region
below 4 GB, but DAC is required for the rest of the transfer. Again, Windows returns two separate addresses and ranges in this case to
prevent memory corruption.
Obviously, DAC or 64-bit adapters and drivers provide the best performance as no buffering of I/O occurs. This buffering is required,
however, whenever the adapter and driver cannot utilize more than 32 bits of address information. All operating systems that utilize PAE
mode addressing support this "double buffering" in some fashion, as a backward compatibility feature. This buffering does have a
performance penalty that is dependent on several factors:
•
•
•
•
Adapter hardware performance
Driver performance
Operating system support provided for double buffering
Amount of physical memory installed in the system
As the physical memory increases, the relative amount of I/O addresses beyond 32 bits also increases in relation to those addresses below
32 bits. In most cases, the operating system transparently provides double buffering, although some Unix variants do not provide any
assistance in this function and require any 32-bit devices and drivers to manage their own double buffering routines and allocations.
Driver Issues
Typically, device drivers must be modified in a number of small ways. Although the actual code changes may be small, they can be difficult.
This is because when not using PAE memory addressing, it is possible for a device driver to assume that physical addresses and 32-bit
virtual address limits are identical. PAE memory makes this assumption untrue.
Several assumptions and shortcuts that could previously be used safely do not apply. In general, these fall in to three categories:
•
•
•
Buffer alignment in code that allocates and aligns shared memory buffers must be modified so that it does not ignore the upper 32 bits of
the physical address.
Truncation of addresses information in the many locations this might be kept must be avoided.
It is necessary to strictly segregate virtual and physical address references so DMA operations do not transfer information to or from
random memory locations.
PAE mode can be enabled on Windows XP SP2, Windows Server 2003 SP1 and later versions of Windows to support hardware-enforced
DEP. However, many device drivers designed for these systems may not have been tested on system configurations with PAE enabled. In
order to limit the impact to device driver compatibility, changes to the hardware abstraction layer (HAL) were made to Windows XP SP2 and
Windows Server 2003 SP1 Standard Edition to limit physical address space to 4 GB. Driver developers are encouraged to read about DEP.
Paging
Most operating systems supporting PAE support virtual memory paging of some nature for the physical memory beyond 4 GB. This usually
occurs with some restrictions such as limiting the boot/system paging file to 4 GB or spreading the paging file (or files) across multiple
operating system-organized volumes (not necessarily physical spindles).
Although this allows the obvious benefits of virtual memory, the downside is the performance impact on applications that have one or more
of the following characteristics:
•
•
•
Use a large amount of physical memory for their data sets
Do a great deal of I/O
Have large executable working sets
Finally, paging support typically comes at the expense of increasing the API set and slowing development and version migration.
User APIs
All operating systems supporting PAE have APIs that allow for use of physical memory by processes beyond the virtual address range
possible on IA-32 processors. These differ primarily in how much support they provide for the items described earlier: memory sharing,
inter-process communications, paging, and so on. A simple and straightforward API set is provided by Windows--the Address Windowing
Extensions (AWE) API set--which consists of only five API calls, with the most complex API being four times larger and involving kernel and
user-level calls.
The proliferation of proprietary APIs--some of which are tied directly to the processor architecture (kernel level)--makes porting applications
from one Unix variant to another expensive, time-consuming, and a constant struggle to balance costs versus performance optimization.
Windows provides an API set which is simple, fast, and completely portable between 32-bit and 64-bit hardware platforms, requiring only a
recompile in order to function.
Page Size
Almost all operating systems supporting PAE use differing page sizes when providing physical memory beyond 4 GB to an application. The
primary exception is Windows, which presents to applications only 4 KB pages on IA-32 platforms (this is different on Itanium-based
platform).
The issue with using varying page sizes for applications is related to additional application complexity required to function correctly with
differing memory allocation sizes, as well as subtle effects related to the underlying assumptions that almost all applications have with page
size. Although research shows a small class of applications can benefit from larger page sizes (2 MB or 4 MB), because each TLB entry
spans a greater address range, the general rule is applications don't benefit from larger page sizes.
Top of page
1.6 Windows and PAE
Windows Version
Support
Windows 2000 Professional
AWE API and 4 GB of physical RAM
Windows XP
Windows XP SP2 and later
AWE API and 4 GB of physical address space
Windows 2000 Server
AWE API and 4 GB of RAM
Windows Server 2003, Standard Edition
Windows Server 2003 SP1, Standard
AWE API and 4 GB of physical address space
Edition
Windows Server 2003, Enterprise Edition
8 processors and 32 GB RAM
Windows Server 2003 SP1, Enterprise
8 processors and 64 GB RAM
Edition
Windows 2000 Advanced Server
8 processors and 8 GB RAM
Windows 2000 Datacenter Server
32 processors and 32 GB RAM (support for 64 GB was not offered because of a lack of
systems for testing)
Windows Server 2003, Datacenter Edition
32 processors and 64 GB RAM
Windows Server 2003 SP1, Datacenter
32 processors and 128 GB RAM
Edition
For more information about PAE and Windows, including guidelines for developers, see PAE Memory and Windows.
Windows Vista Starter Fact Sheet
http://www.microsoft.com/presspass/newsroom/windows/factsheets/WinVistaStarterFS.mspx
2 Windows Vista Starter Fact Sheet
2.1 The Microsoft Windows operating system remains at the center of the ongoing evolution of the personal computer, enabling users to do
more than they ever imagined.
December 2007
Overview
2.1.1.1.1
2.1.1.1.1.1
Related Links
Microsoft
Resources:
The Microsoft Windows operating system remains at the center of the ongoing evolution of the
personal computer, enabling users to do more than they ever imagined. Despite the many
advances, millions of individuals still have not experienced even the most basic benefits of the
PC or accessed the world of social and economic benefits that computing technology can make
possible.
• Windows Client Newsroom
Microsoft Unlimited Potential is the company’s commitment to enabling sustained social and
economic opportunity for the next 5 billion people, a commitment that requires a focus on
providing relevant, accessible and affordable technologies for underserved people everywhere.
2.1.1.1.1.2
In an effort to provide a more affordable and simple introduction to personal computing, and as
a result of ongoing collaborations with international governments to improve citizens’ access to
technology, Microsoft Corp. developed Windows Starter, an operating system designed for
first-time PC owners in emerging technology markets. Windows XP Starter Edition was first
released in Thailand in 2004 and has been subsequently released for use in 139 countries and
in 24 languages. Since the release, more than 2 million families have experienced a PC for the
first time with a Windows Starter-based PC.
• Windows XP Starter Edition Fact
Sheet
Press Releases:
• Microsoft Announces Commitment to
Promote Sustained Social and
Economic Opportunity for the Next 5
Billion People - April 19, 2007
2.1.1.1.1.3
Image Gallery:
• Screenshots - Windows Vista
With the global release of the Windows Vista operating system, Microsoft introduced Windows Vista Starter, the next generation of the
Windows Starter family. Windows Vista Starter is also designed for first-time PC owners in developing markets, but it improves the user
experience through the technological advances of Windows Vista.
Windows Vista Starter Features
Windows Vista Starter provides individuals in developing technology markets and their families with the basic computing benefits they want
with security and reliability features at an affordable price. Windows Vista Starter includes tools and tutorials to make it easier for those less
familiar with computers to learn to use a PC, and runs on affordable entry-level hardware. Benefits of Windows Vista Starter include the
following:
•
•
•
Easier to use. Windows Vista Starter features improved help and support tools, including instructional videos and step-by-step tutorials.
With Windows Vista Starter, first-time home computer users can run up to three programs concurrently with no limit to the number of
windows open.
More reliable. Users gain peace of mind with access to product updates and new updates available only to Windows Genuine Advantage
users.
More affordable. Windows Vista Starter offers all the basic features of Windows Vista at a more affordable price.
Windows Vista Starter includes basic Windows Vista features that allow users to take advantage of computing experiences popular with
first-time computer users, such as the following:
•
•
•
•
•
•
•
Internet connectivity. Windows Vista Starter makes it simple to connect to the Internet and browse the Web.
Software and hardware compatibility. Windows Vista Starter will be compatible with a wide range of Windows-based software
applications and hardware devices, including printers, speakers and cameras.
Windows user interface. The intuitive Windows user interface makes it easy for users to get up to speed quickly.
Security. Windows Vista Starter users will be able to stay up to date and more secure with the latest security updates delivered in
Windows Vista. Parents can also use new parental controls features to help ensure safer use of the computer by their kids.
Communication. Windows Mail and Windows Live Messenger will help make it fun and easy to communicate with friends and family
using e-mail and instant messaging.
Digital photography. When users plug in a digital camera to a Windows Vista Starter-based PC, easy-to-use tools help them transfer and
store their photos, share photos with family and friends, post photos to a Web site, or even make their own prints with one of the many
printers that Windows Vista Starter supports. Windows Vista Starter allows users to access even those pictures located in a shared
folder on a separate computer that is not running Windows Vista Starter.
Digital music and video. Windows Vista Starter includes Windows Media Player 11, which allows users to listen to music, watch videos,
and burn CDs and DVDs. Windows Vista Starter also includes Windows Movie Maker, which lets users create their own movies.
Windows Vista Starter Geographic and Language Availability
Windows Vista Starter ships on low-cost PCs sold by original equipment manufacturers (OEMs) and Microsoft OEM distributors and will be
available in English in all developing technology markets. These markets constitute lower- and middle-income countries as defined by the
World Bank. Windows Vista Starter will be released in 70 languages and more than 139 countries.
Windows Vista Starter Pricing
Windows Vista Starter is the most affordable Windows desktop operating system available. Specific pricing information is available to
participating PC OEMs and Microsoft OEM distributors.
Windows Vista Starter System Requirements
Windows Vista Starter is designed for low-cost, entry-level PCs running value-based processors only. Please see the current and complete
list of processors valid for Windows Vista Starter located under System Requirements here:
http://www.microsoft.com/windows/products/windowsvista/editions/starter/default.mspx.
Windows Vista Starter has the following system requirements:
•
•
•
•
800MHz processor (1GHz or higher processor recommended)
A minimum of 384 MB and a maximum of 1 GB of RAM (512 MB recommended)
15 GB of hard disk space (250 GB maximum)
Super VGA 800 x 600 resolution video adapter
Recommended system requirements:
•
•
•
•
•
CD-ROM or DVD drive
Monitor, keyboard and Microsoft mouse or compatible pointing device
Support for DirectX 9 graphics and 32 MB of graphics memory
Internet access (fees may apply)
Audio output capability
For customer stories and video footage of families using Windows Starter:
Visit http://www.microsoft.com/presspass/presskits/starter-edition/map.
Vista versions
http://windowsitpro.com/article/articleid/47669/pre-pdc-exclusive-windows-vista-processor-and-memory-support-revealed.html
Microsoft is dividing the Vista product line into seven discrete editions (nine if you include European-based N editions)--Vista Starter, Home
Basic, Home Premium, Home N, Professional, Professional N, Small Business, Enterprise, and Ultimate Editions--and will differentiate
them with various features. Part of that differentiation will involve the number and type of processors and the amount of RAM the products
will support.
As you might expect, Vista Starter will be the most constrained edition. It will support one 32-bit microprocessor and up to 256MB of RAM.
The screen resolution will be limited to 1024 x 768 (up from 800 x 600 in Windows XP Starter Edition).
The other editions--Vista Home Basic, Home Premium, Home N, Professional, Professional N, Small Business, Enterprise, and Ultimate
Editions--will ship in both 32-bit (x86) and 64-bit (x64) versions (or will support both architectures). All the home-oriented editions will
support one processor, whereas the business-oriented editions (and Ultimate Edition) will support two.
Home Basic and Home N will be limited to 8GB of RAM, whereas Home Premium will support up to 16GB of RAM on both 32-bit and 64-bit
PCs. All the other products will support the maximum physical memory size on 32-bit systems and up to 128GB of RAM on x64 systems
(although Microsoft could increase that amount in the future because that figure is soft-limited). For more information, see the article
"Windows Vista Product Editions Preview."
Windows Vista Product Editions
http://www.winsupersite.com/showcase/winvista_editions_final.asp
3 Windows Vista Product Editions
Two days before the start of Professional Developers Conference (PDC) 2005 in September 2005, I received exclusive insider information
about the product editions, or SKUs, which Microsoft intends to create for Windows Vista (previously codenamed Longhorn). While the
exact breakdown of the Windows Vista editions had been the subject of much speculation, this list closely matches the editions list I first
published on the SuperSite for Windows in 2004. Since then, in February 2005, Microsoft finally revealed what the final product line-up
would look like and--no surprise--it's almost identical to what I posted several months earlier. Here's how the Windows Vista product
editions break down, according to both the very latest internal Microsoft documentation and what the company's said publicly.
3.1 Windows Vista product edition categories
There will be two general categories of Windows Vista editions, which map closely to the two that exist today for XP ("Home," which
comprises Starter, Home, and Media Center Editions, and "Pro," which includes Professional, Professional x64, and Tablet PC Editions). In
Windows Vista, the two categories are Home and Business.
In the Home category, Microsoft will create four product editions: Windows Vista Starter, Windows Vista Home Basic (and Home Basic N
for the European market), Windows Vista Home Premium, and Windows Vista Ultimate (previously known as "Uber" Edition).
In the Business category, there will are two editions: Windows Vista Business (previously known as Professional Standard Edition; along
with Business N for the European market), and Windows Vista Enterprise (previously known as Professional Premium Edition). A previous
plan to include a third business-oriented edition, dubbed Windows Vista Business, has been dropped.
In all, there are six product editions planned for Windows Vista (or eight, if you count the N Editions as being different). These edition
names are now finalized, though the final feature set for each could change in the coming months.
3.2 Windows Vista product editions
Here's how the product editions look, along with a preview of Microsoft's marketing message for each version.
3.2.1 Windows Vista Starter
Aimed at beginner computer users in emerging markets who can only afford a low cost PC. As with the XP version, Windows Vista Starter
(it was briefly going to be called Windows Starter 2007) is a subset of Vista Home Basic, and will ship in a 32-bit version only (no 64-bit x64
version). Vista Starter will allow only three applications (and/or three windows) to run simultaneously, will provide Internet connectivity but
not incoming network communications, and will not provide for logon passwords or Fast User Switching (FUS). Vista Starter is analogous to
XP Starter Edition. This version will only be sold in emerging markets.
Windows Vista Starter is lacking a number of unique features found in most of the other Vista product editions. There is no Aero user
interface, for example, and no support for Microsoft's new domain-like home networking scheme. Other missing features include DVD
Maker, gaming common controller support, and image editing with enhanced touchup.
The marketing message: For beginner computer users in emerging markets who can only afford a low cost PC, Windows Vista Starter
provides a more affordable and easy introduction to personal computing because it is lower priced, tailored to the needs of beginner
personal computer users, compatible with a wide range of Windows-based applications and devices, and tailored to each market.
3.2.2 Windows Vista Home Basic
A simple version of Windows Vista that is aimed at single PC homes. Windows Vista Home Basic is the baseline version of Windows Vista,
and the version that all other product editions will build from. It will include features such as Windows Firewall, Windows Security Center,
secure wireless networking, parental controls, anti-spam/anti-virus/anti-spyware functionality, network map, Windows Search, Movie Maker,
Photo Library, Windows Media Player, Outlook Express with RSS support, P2P Messenger, and more. Windows Vista Home Basic is
roughly analogous to Windows XP Home Edition. This version is aimed at general consumers, Windows 9x/XP Starter Edition upgraders,
and price sensitive/first-time buyers. Like Vista Starter, Vista Home Basic will not support the new Aero user interface.
The marketing message: For mainstream Windows customers, Home Basic is where it all begins. Here, Microsoft will be pushing "peace of
mind" and "performance," and will promise consumers a faster, more secure and reliable productivity experience. Home Basic is secure by
default and easy to keep secure. You can trust Windows with your most important tasks and data and complete everyday tasks faster.
For a look at Windows Vista Home Basic, see my screenshot gallery.
3.2.3 Windows Vista Home Premium
As a true superset of Home Basic, Windows Vista Home Premium will include everything from Home Basic, as well as Media Center and
Media Center Extender functionality (including Cable Card support), DVD Maker DVD authoring, Tablet PC functionality, Mobility Center
and other mobility and presentation features, auxiliary display support, P2P ad-hoc meeting capabilities, Wi-Fi auto-config and roaming,
unified parental controls that work over multiple PCs, backup to network functionality, Internet File Sharing, Offline Folders, PC-to-PC sync,
Sync Manager, and support for Microsoft's upcoming Quattro Home Server, a Windows Server 2003 R2-based server product aimed at the
home market. Windows Vista Premium is similar to XP Media Center Edition, except that it adds numerous other features and functionality,
including Tablet PC support. My guess is that this will be the volume consumer offering in the Windows Vista timeframe (today, XP Pro is
the dominant seller). This version is aimed at PC enthusiasts, multiple-PC homes, homes with kids, and notebook users.
The marketing message: Home Premium turns it up a notch. In addition to the baseline functionality offered in Home Basic, this version
focuses on such things as integrated entertainment (movies, memories, and more), mobility (media and productivity on the go), and
connected living (connect with family, friends, and home). Home Premium supplies whole-home entertainment and personal productivity
throughout the home and on the go.
For a look at Windows Vista Home Premium, see my screenshot gallery.
3.2.4 Windows Vista Business
A powerful, reliable and secure OS for businesses of all sizes. Windows Vista Business will include domain join and management
functionality, compatibility with non-Microsoft networking protocols (Netware, SNMP, etc.), Remote Desktop, Microsoft Windows Web
Server, and Encrypted File System (EFS). Additionally, Vista Business will include Tablet PC functionality. Windows Vista Business is
roughly analogous to XP Pro today. This version is aimed at business decision makers and IT managers and generalists.
The marketing message: Vista Business is a powerful, reliable, and secure operating system. It helps PC users be more effective at work
and offers improved connectivity and access to information, so that companies can realize better return on their IT investment.
For a look at Windows Vista Business, see my screenshot gallery.
3.2.5 Windows Vista Enterprise
Optimized for the enterprise, this version will be a true superset of Windows Vista Business, available only via volume license to Software
Assurance (SA) customers. It will include unique features such as single-instance Virtual PC, the multi-language user interface (MUI), and
the Secure Startup/full volume encryption security technologies ("Cornerstone"). There is no analogous XP version for this product. This
version is aimed at business decision makers, IT managers and decision makers, and information workers/general business users.
The marketing message: Vista Enterprise provides an advanced application compatibility solution that will be crucial to many large business
users, can be deployed to multiple language locales using a single image, and provides Secure Startup functionality for the ultimate in
security on the go. It is the client OS that is optimized for the enterprise. Vista Enterprise reduces IT cost and complexity by providing tools
that protect company data, reduce the number of required disk images, and ensure the compatibility of legacy applications.
3.2.6 Windows Vista Ultimate
The best operating system ever offered for a personal PC, optimized for the individual. Windows Vista Ultimate is a superset of both Vista
Home Premium and Vista Business, so it includes all of the features of both of those product versions, plus adds Game Performance
Tweaker with integrated gaming experiences, a Podcast creation utility (under consideration, may be cut from product), and online "Club"
services (exclusive access to music, movies, services and preferred customer care) and other "Vista Ultimate Extras" offerings (also under
consideration, may be cut from product). Microsoft is still investigating how to position its most impressive Windows release yet, and is
looking into offering Vista Ultimate owners such services as extended A1 subscriptions, free music downloads, free movie downloads,
Online Spotlight and entertainment software, preferred product support, and custom themes. There is nothing like Vista Ultimate today. This
version is aimed at high-end PC users and technology influencers, gamers, digital media enthusiasts, and students.
The marketing message: Vista Ultimate is the "no compromises" version of Windows Vista. It provides the best performance, most secure
and complete connection to the office, and is optimized for the individual. Everything you need for work or fun is included. It is the best
operating system ever offered for the personal PC.
For a look at Windows Vista Ultimate, see my screenshot galleries.
3.2.7 N Editions
Finally, I should note that Microsoft is planning to offer so-called N Editions of Windows Vista for the European market, in order to meet the
requirements of an antitrust ruling there. Windows Vista N Editions--Vista Home Basic N and Vista Business N--will mirror the Vista Home
Basic and Vista Business versions, respectively, but will not include Windows Media Player and other media-related functionality.
3.3 Features breakdown
Many people are curious about which features will be made available in each product edition. Here's a partial list.
Conceptual diagram of the Windows Vista product editions and how they relate to one another. Note that Small Business Edition will not be offered.
Key to the table:
Str - Windows Vista Starter
Home N - Windows Vista Home N (Europe only)
Home B - Windows Vista Home Basic
Home P - Windows Vista Home Premium
Bus N - Windows Vista Business N (Europe only)
Bus - Windows Vista Business
Ent -Windows Vista Enterprise
Ult - Windows Vista Ultimate
Fundamentals
Feature
SafeDocs backup and restore
Backup (scheduled)
Backup (network-based)
Shadow copy client
Encrypted File System (EFS)
Supports migration from XP
Productivity
Feature
Desktop Window Manager (DWM)
Aero glass, animations, visual effects
Productivity features (rolodex, tab previews, task bar previews)
Unlimited screen resolution support
Fast User Switching (FUS)
Communications
Str
No
No
No
No
No
No
Home N
Yes
No
No
No
No
Yes
Home B
Yes
No
No
No
No
Yes
Home P
Yes
Yes
Yes
No
Yes
Yes
Bus N
Yes
Yes
Yes
Yes
Yes
Yes
Bus
Yes
Yes
Yes
Yes
Yes
Yes
Ent
Yes
Yes
Yes
Yes
Yes
Yes
Ult
Yes
Yes
Yes
Yes
Yes
Yes
Str
No
No
No
No
Home N
Yes
No
No
Home B
Yes
No
No
Home P
Yes
Yes
Yes
Bus N
Yes
Yes
Yes
Bus
Yes
Yes
Yes
Ent
Yes
Yes
Yes
Ult
Yes
Yes
Yes
1024x768
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Feature
RDP/Remote Desktop
P2P Meeting Place (ad-hoc meetings, people discovery, presentation
broadcast)
Windows Web Server (optional)
Windows Fax client
Digital Media & Entertainment
Feature
DVD Video Authoring
Direct Media Mode
Media Center (including Extender and games)
Number of remote Media Center sessions supported
Movie Maker HD Publishing
Advanced Photography features
Premium Games (3D Chess, Shanghai Solitaire)
Windows Media Player 11 and related components
Networking
Feature
Number of supported network connections
Domain join support
1:1 Network projection
SNMP support
Internet Connection Sharing (ICS)
Mobility
Feature
PC-to-PC Sync
Mobility Center
Tablet PC functionality
Auxiliary Display support
Offline folders with client-side caching
PC management
Feature
Subsystem for UNIX-based Applications (SUA)
Secure Startup (Cornerstone)
Single Session Virtual PC
Multi-Language User Interface (MUI)
Str
No
Home N
No
Home B
No
Home P
No
Bus N
Yes
Bus
Yes
Ent
Yes
Ult
Yes
No
No
No
No
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
No
Yes
Yes (opt)
Yes
Yes (opt)
Yes
Yes (opt)
Yes
Yes (opt)
Str
No
No
No
n/a
No
No
No
Yes
Home N
No
Yes
No
n/a
No
No
No
No
Home B
No
Yes
No
n/a
No
No
No
Yes
Home P
Yes
Yes
Yes
5
Yes
Yes
Yes (Opt)
Yes
Bus N
No
Yes
No
n/a
No
Yes (opt)
Yes (Opt)
No
Bus
No
Yes
No
n/a
No
Yes (opt)
Yes (Opt)
Yes
Ent
No
Yes
No
n/a
No
Yes (opt)
Yes (Opt)
Yes
Ult
Yes
Yes
Yes
5
Yes
Yes (opt)
Yes (Opt)
Yes
Str
0
Home N
5
Home B
5
Bus N
10
Bus
10
Ent
10
Ult
10
No
No
No
Yes
Yes
Yes
Yes
No
Yes
No
No
Yes
Yes
No
Yes
Yes
Home P
10
No
only
Yes
Yes
Yes
Yes
Yes (Opt)
Yes (Opt)
Yes
Yes (Opt)
Yes
Yes
Yes (Opt)
Yes (Opt)
Yes
Yes (Opt)
Yes
Str
No
No
No
No
No
Home N
No
No
No
No
No
Home B
No
No
No
No
No
Home P
Yes
Yes
Yes (Opt)
Yes
No
Bus N
Yes
Yes
Yes (Opt)
Yes
Yes
Bus
Yes
Yes
Yes (Opt)
Yes
Yes
Ent
Yes
Yes
Yes (Opt)
Yes
Yes
Ult
Yes
Yes
Yes (Opt)
Yes
Yes
Str
No
No
No
No
Home N
No
No
No
No
Home B
No
No
No
No
Home P
No
No
No
No
Bus N
No
No
No
No
Bus
No
No
No
No
Ent
Yes (Opt)
Yes
Yes (Opt)
Yes
Ult
Yes (Opt)
Yes (Opt)
Yes (Opt)
Yes (Opt)
3.4 Processor and memory support
What about processor and memory support? Most Windows Vista product editions will be available in both 32-bit and 64-bit (x64) versions. Here's how the various versions support each processor type, and how much RAM they allow.
Processor and memory support
Feature
Supports 32-bit processors (x86)
Amount of RAM supported on 32-bit systems
Supports 64-bit processors (x64)
Amount of RAM supported on x64 systems
Number of physical CPUs supported
Str
Yes
Home N
Yes
Home B
Yes
Home P
Yes
256 MB
8 GB
8 GB
16 GB
No
n/a
1
Yes
8 GB
1
Yes
8 GB
1
Yes
16 GB
1
Bus N
Yes
Max
physical
Yes
128 GB+
2
Bus
Yes
Max
physical
Yes
128 GB+
2
Ent
Yes
Max
physical
Yes
128 GB+
2
Ult
Yes
Max
physical
Yes
128 GB+
2
There's been some confusion about the difference between multiple processors and multiple processor cores (for example, both Intel and AMD are currently selling dual-core CPUs, and quad-core chips are on the way). While all of the Vista product
editions support only one or two physical processors, none are limited to the number of processor cores they will support.
3.5 Selling Windows Vista
According to internal Microsoft documentation, the goal of the product edition differentiations in Windows Vista is to provide "clear value proposition" to all customer segments and take XP-era innovations, such as the Media Center and Tablet PC
functionality, to the mainstream. Windows Vista is also being positioned as a transitionary product for the x64 platform: Almost all Windows Vista editions will be offered in both x86 (32-bit) and x64 (64-bit) versions, and these versions will ship in the
same box. So, for example, when you purchase Vista Home Premium, the version you get will depend on which type of PC you have: If it's an x64-based PC, the x64 version will be installed. Microsoft expects to transition its client product lines
completely to x64 after the release of Windows Vista.
What's scary here, of course, is how widely Microsoft is expanding the Windows product line. As with its Office family of products (see my Office 2007 FAQ for details), Microsoft is stretching things a bit with this wide number of product editions, and
this will lead to consumer and business confusion, which is never a good thing. When the company revealed that they were componentizing Windows Vista in order to make it easier for the company and its PC maker partners to create various product
editions on the fly (read a discussion about this topic in my showcase, The Road to Windows Longhorn 2003), few people expected them to take advantage of the situation like this. The sheer number of Windows Vista versions is going to cause
massive consumer confusion, and some of these versions will likely be orphaned after they prove to be targeting niche markets. That will lead to further migration confusion when the time to upgrade comes.
In any event, there's a lot of information to digest here, but I know that SuperSite readers have been waiting for this for ... well, years. Enjoy!
--Paul Thurrott
March 2, 2006