Chapter 3:
Hardware: Input, Processing, and Output Devices
Most information in this presentation has been copied from the Dell.com web site
What is Hardware?
 Hardware consists of any machinery (most of which use
digital circuits) that assist in the input, processing, storage,
and output activities of an information system.
What is a Computer System?
 A computer system is a special subsystem of an
organization’s overall information system used to input,
process, store and output data and information.
 Putting together a complete computer system is more than
just connecting computer devices. Components must be
selected and organized with an understanding of the
tradeoff between overall system effectiveness and
efficiency, and considerations of cost, control and
complexity.
 When selecting computer system devices, you must
consider the current and future needs of the overall
information system.
Computer System Hardware
Components
 Computer system hardware components include devices
that perform the functions of input, processing,
communication, data storage and output.
Part I: How to Buy a Computer
Most information in this presentation has been copied from the Dell.com web site
DimensionTM XPS Gen 4: NEW! Extreme
Performance with Expandability
The most advanced Dimension ever built @ $5,573
(configured system)
 Pentium® 4 Processor w/ HT Tech Extreme Edition
(3.40GHz, 800 FSB)
 4GB Dual Channel DDR2 SDRAM at 533MHz (4x1GB)
 400GB Serial ATA Hard Drive (7200RPM)
 256MB PCI Express™ x16 (DVI/VGA/TV-out) ATI
Radeon™ X850 XT PE
 20 inch Ultrasharp™ 2001FP Digital Flat Panel
 Dual Drives: 48x CD-RW Drive + 16x DVD+/-RW w/
double layer write capable
 1GB Compact Flash Card
 Dell Wireless Keyboard and Optical Mouse
 Dell 5650 5.1 Surround Sound Speaker System with
Subwoofer
 IEEE 1394 Adapter
 56K PCI Telephony Modem
Pentium® 4 Processor w/ HT Tech Extreme
Edition (3.40GHz, 800 FSB)
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Your processor is the brain of your computer. It is also called the central processing unit
(CPU). It interprets and executes instructions of computer programs or the operating
system. In terms of computing power, the CPU is the most important element of a
computer system. The combination of processor clock speed, architecture, cache, and
front side bus decides the performance of a processor.
Clock Speed: Speed of the processor's internal clock which dictates how fast the processor
can process the data. Clock speed is usually measured in GHz (gigahertz, or billions of
pulses per second).
Architecture: Basic design of a microprocessor. It may include processor technology
and/or other architectural enhancements.
Cache: A temporary storage for frequently accessed or recently accessed data. Having
certain data stored in a cache speeds up the operation of the computer. Cache size is
measured in megabytes (MB) or kilobytes (KB). Level 1 Cache is a small, fast memory
cache that is built in to the main chip and helps speed access to important and frequentlyused data. Level 2 Cache is a collection of built-in memory chips, slower than the Level 1
Cache but faster than the main memory area. Level 2 (L2) Cache can help speed the
operation of some applications.
Front Side Bus: The connecting path between the processor and other key components
such as the memory controller hub. FSB speed is measured in GHz or MHz.
4GB Dual Channel DDR2 SDRAM at
533MHz (4x1GB)
 Random Access Memory (RAM) is the workhorse behind the performance of
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your computer. RAM temporarily stores information from your operating
system, applications, and data in current use. This gives your processor easy
access to the critical information that makes your programs run. The amount of
RAM you have determines how many programs can be executed at one time
and how much data can be readily available to a program. It also determines
how quickly your applications perform and how many applications you can
easily toggle between at one time. Simply put, the more RAM you have, the
more programs you can run smoothly and simultaneously.Upgrading your
memory is truly one of the most cost-effective ways you have to boost system
performance.
Tests show that increasing memory from 128MB to 256MB increases system
performance up to 37%. Increasing memory from 128MB to 512MB improves
system performance up to 50%.
DDR SDRAM: Double Data Rate Synchronous Dynamic Random Access
Memory is memory that provides higher bandwidth than ordinary SDRAM
memory.
Frequency: The number of repetitions in a signal or waveform, measured in
Mega-Hertz (MHz). A higher frequency improves system performance and
speed.
Dual Channel: Memory technology that delivers twice the peak bandwidth of
single channel memory.
400GB Serial ATA Hard Drive (7200RPM)
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The hard drive is the primary storage unit of the computer. It is where the operating
system, applications, files and data are kept. If you use your computer for digital video,
audio file storage or you like to work with intense applications, you should consider
buying a larger size hard drive or RAID.
RAID hard drives combine the performance and security of multiple hard drives into
one disk. RAID 0 (data striping) for maximum performance or RAID 1 (data mirroring)
for data security. Performance users such as video editors often utilize RAID 0. Users to
whom data integrity is vital often utilize RAID 1. With RAID 0 all capacity on both hard
drives is usable. With RAID 1 only half the capacity is usable and the other half is
devoted to back-up.
Storage Capacity: Why buy a higher capacity hard drive? - Higher capacity drives
allow you to store larger amounts of data. This may prevent you from having to upgrade
your system or hard drive in the future due to lack of storage space. If you download
content or manage content on your system, you may want to buy a larger drive initially
as well.
Rotational Speed: Why Buy a Higher RPM Drive? - Rotational speed is a major
factor in hard drive selection as it determines how quickly data can be retrieved. Typical
rotational speeds are 5400 RPM or 7200 RPM for desktops, and 4200 RPM or 5400
RPM for notebooks. The higher the RPM (revolutions per minute), the less time you'll
spend waiting for your computer to access files.
Interface (Parallel or Serial): Is interface important? - The interface is the link
between the hard drive and the computer used to transfer data. It is important because it
regulates the speed of data throughput from the system to the hard drive. The new SATA
(Serial Advanced Technology Attachment) is the evolutionary follow-on to IDE. SATA
is capable of higher data throughput than the UATA-100 interface.
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256MB PCI Express™ x16 (DVI/VGA/TVout) ATI Radeon™ X850 XT PE
A video card is the part of your computer that transforms video data into the visual display
you see on your monitor. The video solution plugs into your computer's motherboard, and is
responsible for decoding and processing the video signal. The quality of video you see on
your monitor depends on both the video card and the monitor you choose. More video card
memory and faster graphics processors can result in more stunning and enjoyable visual
effects when running games and programs with detailed graphic design.
Memory: Video cards have their own memory, which is reserved for storing graphical
images. Video memory on a video card frees the computer's RAM, so the computer's
memory does not have to store graphics. Video memory is available in standard sizes:
32MB, 64MB, 128MB, etc. Typically, a card with a higher memory capacity will be capable
of more advanced rendering and support for 2-D and 3-D graphics. If you are planning on
doing presentations, desktop publishing, gaming, or video editing, you should consider at
least 128MB video memory.
Processor: In addition to memory, video cards have their own graphics processor for
creating images. A graphics processor is specially designed for computing graphical
transformations, and it can achieve faster graphics results than the general-purpose CPU
used by the computer. An integrated graphics solution uses the CPU of your computer to
create graphics, so it typically will not render pictures as quickly as a video card with its
own processor. It takes thousands of calculations to produce even basic images on your
monitor. The video card processor is also known as the controller or graphics engine.
PCI Express: PCI Express (PCIe) is the latest interface specification designed to improve a
system's graphic performance by increasing its bandwidth. It helps speed the
communication flow between the CPU and the graphics controller. This enhancement
allows texture maps of greater size, detail, and realism enabling 3D applications to run
faster because of even higher bandwidth compared to AGP.
20 inch Ultrasharp™ 2001FP Digital Flat Panel
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Size: Monitors are measured in inches and refer to the diagonal length from one corner of
the monitor box to the other. The actual viewable area (or screen measurement) is the
measurement in parentheses and labeled VIS (viewable image size). Monitors are usually
listed as: 17-in (16.0 viewable). This is very important when comparing flat panels to
CRT's. A flat panel usually has the same VIS as its size category; a 17" flat panel has a
17.0" VIS. However a 17" CRT may have a 16.0" VIS or less as the width of the CRT
bezel is included in the monitor size measurement. Also keep in mind that most
conventional CRT monitors are as deep as they are wide so if space is a limitation, you
should consider purchasing a flat panel display.
Flat panel quality is determined by resolution. Resolution refers to the number of
individual pixels contained on a display. The higher the resolution, the more pixels can fit
onto the screen and so the sharper and more detailed images can be displayed. Resolution
together with contrast ratios, brightness and viewing angles determine the overall quality
of a flat panel.
CRT quality is measured in dot pitch or strip pitch. Dot pitch is the measure of space
between a display's pixels; the smaller the pitch, the sharper the images. A measurement of
.27mm is average for dot pitch. The monitor's viewable area, refresh rate and dot pitch all
directly affect the maximum resolution a monitor can display.
Active Matrix TFT LCD technology displays sharp, brilliant images with resolutions from
1024 x 768 to 1600 x 1200 pixels, depending on display model.
A wide viewing angle allows viewing from various angles without compromising image
quality allowing for viewing flexibility or multiple user viewing.
Digital DVI functionality provides seamless digital connection, helping to maintain image
integrity.
Dual Drives: 48x CD-RW Drive + 16x
DVD+/-RW w/ double layer write capable
 The DVD+/-RW Burner is a great all-in-one drive, allowing you to
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read or burn DVD+R, DVD-R, DVD+RW, DVD-RW, CD-R and CDRW discs, as well as read CD-ROM and DVD-ROM.
What is Double Layer? The combination of a double layer DVD+/RW drive and double layer capable media support writing up to 8.5GB
of data or video to a double layer DVD+R or DVD-R.
16x is a measurement of CD or DVD drive speed. Each x translates to
either 153,600 bytes of data per second, the data rate of the CD-audio
or 1,250,000 bytes per second, the data rate of the DVD-video.
What is a CD-RW? A CD-RW will allow you to easily create your
own custom music CDs and data CDs for data back-up or data transfer
purposes. It will also allow you to store and share video files, large
data files, digital photos, and other large files with other people that
have access to a CD-ROM drive. This drive will also do anything your
CD-ROM will do. It reads all your existing CD-ROMs, Audio CDs,
and CDS that you create with your CD burner.
DVD+RW is a DVD-Rewritable disc, a DVD that can be written to
erased many times (up to 1000).
1GB Compact Flash Card / Other Storage
 Get extra memory to store important files and presentations for productivity on
the go - or store your favorite MP3 music or eBooks for entertainment. This 1
GB CompactFlash® (CF) Card retains data even if the system's power supply
is switched off, thus offering significant data protection. The CF card features
an integrated controller which stores all IDE and ATA commands, making the
CF card fully compatible with all operating systems, utilities and application
programs that support industry-standard IDE disk drives. CompactFlash
requires no special Flash File systems or drivers. It works in systems that
support only 3.3 V or only 5 V. The non-volatile solid-state card uses no
moving parts, thus maximizing battery power.
 The USB Memory Key lends itself to a wide variety of innovative uses. The
product is an active device with its own central processing unit (CPU) and is
capable of supporting and running multiple applications directly from the
product.
 Floppy drives record up to 1.44 MB of data on a rugged 3.5" removable
magnetic diskette. Floppy disk drives have been available in the industry for
many years and are ideal for customers who want to easily and inexpensively
transfer small files from one computer to another, backup small amounts of
data, or create a boot disk(s).
Dell Wireless Keyboard and Optical Mouse
 The keyboard is the primary tool used to interface with the computer. It is a
necessary and often overlooked component to an enjoyable computer experience.
 Key factors when choosing the right keyboard include comfort, convenience and
ease of use. For customers who wish to minimize the appearance of wires/cords
on their desktop, a wireless keyboard and mouse solution is available.
 Radio technology is used to communicate between the keyboard and the receiver
There are three general types of keyboard technology:
 PS/2 - PS/2 technology is an older, stable and very reliable technology. PS/2
keyboards plug into the PS/2 connector ports located on the back of the computer.
 USB - USB technology is newer than PS/2: It is generally more responsive to the
touch than PS/2. USB keyboards plug into the USB connector ports located on the
back of the computer.
 Wireless - Wireless technology is fairly new in the marketplace: It was created to
answer customer needs for a clutter free desktop. Wireless products consist of the
actual keyboard as well as a receiver. The receiver communicates between the
computer and the wireless keyboard using either radio or infrared technology.
Some wireless solutions include both the wireless keyboard and the wireless
mouse.
 Great mouse performance! Optical technology records motion more precisely,
glides more easily than a mouse ball, and has no moving parts to wear out or
clean. The 400/800 DPI sensor has accurate response for applications such as
gaming, photo editing, and graphic design. Programmable buttons provide easy
access to functions used most often.
Dell 5650 5.1 Surround Sound Speaker
System with Subwoofer
 Speakers are a good choice for improving the quality of multimedia
presentations, online training / web casts, music listening, gaming, and
DVD playback on your system.
 Dell 5650 5.1 Surround Speakers: Total surround sound, great for
listening to DVD-Audio, DVD-Video, or that 3D audio gaming
experience. Center channel speaker features unique flat panel
mountable capability.
 Multi-Channel Audio: Many popular multimedia formats support
multi-channel audio or surround sound. Dolby Digital 5.1 DVD
movies and DirectSound3D games support multi-channel playback. In
layman's terms, think of a channel as a satellite speaker and the ".1" as
a subwoofer. If you want to enjoy 5.1 surround, your system or sound
card must support 5.1 multi-channel audio. Stereo is two channel,
meaning two speakers or two speakers plus a subwoofer.
IEEE 1394 Adapter
 Purchase this adapter if you want to capture video from a
digital camcorder or connect external hard drives to your
computer. The IEEE 1394 adapter is a connection standard
like the USB (Universal Serial Bus) and because of its
ability to move data quickly (up to 400Mbits/sec) it is
primarily used to capture video from digital camcorders or
to connect external hard drives.
Part II: What We Missed in Part I?
Computer System Types
 Personal Computers (PCs) are used by individual users
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(desktops, laptops, notebooks, sub-notebooks, Handheld
(palmtop)
Network computers are cheaper versions of PCs and are
primarily used to access the Internet and other networks
Workstations are high-end microcomputers and use RISC
processors
Midrange computers (mini computers) are systems that
accommodate several users at a time
Mainframe computers are large, powerful computers often
shared by hundreds of concurrent users
Supercomputers are the most powerful computer systems
used often in military and research organizations trying to
solve complex problems.
The Mainboard
A mainboard is the foundation of the computer.
Important mainboard components:
 Microprocessor Socket houses the Central Processing Unit
(CPU).
 Memory Sockets are used to add memory to the computer.
 Expansion slots house controller cards.
 Buses transfer the data in the mainboard.
 BIOS (basic input/output system) gives the first
instructions to the computer (look for BIOS that supports
Plug and Play).
 Chip Sets control the memory I/O, the bus I/O, the
interrupt requests (IRQs) and in many cases the hard disk
controllers. If the CPU is the heart of the computer, chip
sets are the pacemakers.
The Processor
The processor or Central Processing Unit (CPU) is the
heart of the computer because it ultimately controls all its
functions. There are:
 CISC (Complex Instruction Set Computing) and
 RISC (Reduced Instruction Set Computing) processors
CPU characteristics
 Machine cycle time is the time in which a machine cycle
occurs (instruction + execution phases). Machine cycle is
usually measured in time intervals (i.e.microseconds) or
MIPS (million instructions per second).
 Wordlength is the number of bits the CPU can process at
any one time. Wordlenght is measured in bits (i.e., 64 bits).
 Bus line width is the number of bits a bus line can transfer
from the CPU to other components and is also measured in
bits (i.e., 64 bits).
Memory
 Random Access Memory (RAM) is a volatile primary
storage location that the processor uses to store our data
during processing.
 Read Only Memory (ROM) is a non volatile memory and as
a result its content is permanent.
 Cache memory (SRAM-Static RAM) is a very fast and
expensive memory type that holds data frequently used by
the CPU so the CPU does not have to rely only on slower
RAM. When we talk about cache, we are usually talking
about Level 2 cache (external to the processor). Many
vendors will offer cache-less PCs at a lower price.
Controller Cards
 Controller cards are hardware devices that control the
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operations of hardware peripherals. Every component that
is attached to the computer needs a controller card.
The monitor needs a monitor controller card to function
The hard drive and the floppy drives need a controller card
Speakers attached to the computer need a sound card
A CD-ROM needs a CD-ROM controller card
The controller card must be compatible with the peripheral
and the mainboard (i.e., a VGA monitor needs a VGA
controller card, a SCSI CD-ROM needs a SCSI controller
card)
Ports
 Ports are hardware devices used to connect the computer
with other hardware components called peripherals. Ports
are the attachment points of these peripherals to the
computer.
 Some peripheral hardware components are: the mouse, the
printer and the CD-ROM drive
 Common port types are:
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The Serial Port
The Parallel Port
The Game Port
USB Port
Firewire
Other Input Devices
 Voice-recognition devices
 Digital computer cameras
 Scanning devices
 Optical data readers (OCR and OMR)
 Magnetic ink character recognition (MICR)
 Point-of-sale (POS) devices
 Automatic teller machines (ATM) devices
 Pen input devices
 Touch-sensitive screens
 Bar code scanners