Chapter 3:
Hardware: Input, Processing, and Output Devices
Most information in this presentation has been copied from the Dell.com web site
Agenda
 Computer System
 How to buy a computer
 Other Computer System Hardware
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, it is necessary to
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 of an information
system.
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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The processor is the brain of a 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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the computer. RAM temporarily stores information from the operating system,
applications, and data in current use. This gives the processor easy access to
the critical information that makes the programs run. The amount of RAM
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 the
applications perform and how many applications can easily be toggled
between at one time. Simply put, the more RAM the computer has, the more
programs can be run smoothly and simultaneously. Upgrading your memory is
truly one of the most cost-effective way to boost the 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
the single channel memory.
400GB Serial ATA Hard Drive (7200RPM)
 The hard drive is the primary storage unit of the computer. It is where the
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operating system, applications, files and data are kept.
RAID hard drive combines multiple hard drives into one disk to achieve the
performance and security. RAID 0 (data striping) for maximum performance
or RAID 1 (data mirroring) for data security. The video editor often utilizes
RAID 0. User with the data integrity concern, often utilizes 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 can store larger amount of data. It is necessary to buy a larger
size hard drive or RAID in order to store digital video, audio file storage or to
work with intense applications.
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 is required for the computer to access the file.
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 the computer that transforms video data into the visual display
you see on the monitor. The video card plugs into the computer's motherboard, and is
responsible for decoding and processing the video signal. The quality of video on the
monitor depends on both the video card and the monitor. 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 card has 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. It is better to have at least
128MB video memory for performing the tasks of presentation, desktop publishing, gaming,
or video editing.
Processor: In addition to memory, video card has its own graphics processor for creating
images. A graphics processor is specially designed for computing graphical transformations,
and achieving 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 that is
slower than a video card with its own processor since it takes thousands of calculation to
produce even basic images on the 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 with greater size, detail, and realism. It also enables 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: The monitor is 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 as VIS (viewable image size). The monitor is
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 the most
conventional CRT monitors are as deep as they are wide. Purchasing a flat panel display is
more suitable for the limited space environment.
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. The
resolution together with contrast ratio, brightness, and viewing angle 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 display quality of a monitor.
Active Matrix TFT LCD technology displays sharp, brilliant images with resolution
ranging from 1024 x 768 to 1600 x 1200 pixels, depending on the display model.
A wide viewing angle allows viewing from various angles without compromising image
quality for the viewing flexibility or the 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 an all-in-one drive to read or burn DVD+R,
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DVD-R, DVD+RW, DVD-RW, CD-R and CD-RW 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 for the data rate of the CDaudio or 1,250,000 bytes per second for the data rate of the DVDvideo. ?
What is a CD-RW? A CD-RW will allow an user to create custom
music CDs and data CDs for data back-up or data transfer purposes. It
can also 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.
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
 The 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.?
 The USB Memory Key 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 drive records up to 1.44 MB of data on a rugged 3.5"
removable magnetic diskette. Floppy disk drive has been available in
the industry for many years and is ideal for inexpensively transferring
small file from one computer to another, backing up the small amount
of data, or creating a boot disk
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 the 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.
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 the
computer 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. The stereo is two
channels, meaning two speakers.
IEEE 1394 Adapter
 This adapter enables the computer to capture video from a
digital camcorder or connect external hard drives. 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.
56K PCI Telephony Modem
Modems will be discussed in chapter 6.
Part II: Other Computer System
Hardware
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
Execution of an Instruction
The execution of a machine-level instruction involves two phases: the
instruction and the execution phase.
 In the instruction phase (I-time):
– Step 1: Fetch instruction – The control unit accesses the instruction from
memory
– Step 2: Decode instruction – The instruction is decoded and relevant data is
moved from memory to the register storage area, and the location of the
next instruction is identified
 In the execution phase (E-time):
– Step 3: Execute the Instruction- The ALU does what is instructed to do
(arithmetic operation or comparison)
– Step 4: Store results- The results are stored in registers or memory
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Measurements
Microseconds (1 millionth)
Nanoseconds (1 billionth)
Picoseconds (1 trillionth)
MIPS
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).
RAM and ROM
 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
 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
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
Points to Remember
 Computer System
 How to buy a computer
 Other Computer System Hardware