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NEW PERSPECTIVES COMPUTER CONCEPTS Chapter 2 Computer Hardware... Chapter Contents * Section A: Personal Computer Basics * Section B: Microprocessors and Memory * Section C: Storage

NEW PERSPECTIVES

COMPUTER CONCEPTS

Chapter 2

Computer Hardware

Chapter Contents

* Section A: Personal Computer Basics

* Section B: Microprocessors and Memory

* Section C: Storage Devices

* Section D: Inout and Output Devices

* Section E: Hardware Security

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* Personal Computer Systems

* Desktop and Portable Computers

* Home, Media, Game, and Small Business

systems

* Buying Computer System Components

The term form factor

refers to the size and dimensions of a

component, such as a

system board or

system unit

A desktop computer fits

on a desk and runs on

power from an electrical

wall outlet

Desktop and Portable Computers

* A portable computer is a small, lightweight

personal computer

* A notebook computer (also referred to as a

laptop), is a small, lightweight portable

computer that opens like a clamshell to

reveal a screen and keyboard

* A tablet computer is a portable computing

device featuring a touch-sensitive screen that can be used as a writing or drawing pad

Desktop and Portable Computers

Home, Media, Game,

and Small Business Systems

* A home computer system offers a hardware

platform with adequate, but not super-

charged support for most computer

applications

* Some of the most cutting-edge computers

are designed for gaming

* Computers marketed for small business

applications tend to be middle-of-the-line

models pared down to essentials

* Decide on a platform (Mac, PC, Linux)

* Look at ads in computer magazines and at

computer/electronic stores

* Understand the computer jargon

* Expect to pay anywhere from a few hundred

to several thousand dollars

Upgrade

Replace processor Add memory

Add external

hard drive Replace internal hard

disk drive

Replace

grapnics care

Svitch to wireless keyboard and mouse

Add USB port or dicital Camera memory card reader

Add second display screan

speakers Replace CD or DVD drive

Time 1-5 hours 30-60 minutes 10-15 minutes 1-2 hours

1 hour

15 minutes

15 minutes 5-10 minutes

* Instead of buying a new computer, you might consider upgrading

Cost (US$) Difficulty

Difficult and not

recommended

Moderate Easy Somewhat difficult Moderate Easy Easy

Easy

Easy Moderate

Accessibility

nternal internal Extemal internal Internal External Extemal Extemal Extemal Internal

Package

Technology

Specification Family Ext Family

Instructions

Clocks Core Speed

6 Ext Model é Revision mBO

MMX, SSE SSE2, SSE3

Cache

174.5 MHz L1 Data 32 KBytes

x 5.0 L1 Code 32 KBytes 34.9 MHz Level 2 2048 KBytes

Cores 1 Threads 1

Version 1.37

Extreme Edition Celeron Celeron M

Pentium M Mobile Pentium 4

Desktops, portables

Servers

Servers Servers,

desktops Servers, desktops Desktops

Desktops Portables

Notebooks

PDAS Notebooks,

Sempron

Mobile Sempron

Servers Desktops,

portables Notebooks, PDAs

Desktops Notebooks, PDAs

Random Access Memory

* Random Access Memory is a temporary

holding area for data, application program

instructions, and the operating system

Random Access Memory

* Microscopic capacitors hold the bits that

represent data

* Most RAM is volatile

— Requires electrical power to hold data

The two charged capaci- tors at this RAM address represent the letter “A.”

A different sequence of charged capacitors represents the letter “B.”

Another sequence of charged capacitors represents the letter "C.”

~ Random Access Memory

* RAM capacity is expressed in megabytes or gigabytes

* Personal computers typically feature

between 256MB and 2GB of RAM

* An area of the hard disk, called virtual

memory, can be used if an application runs out of allocated RAM

Random Access Memory

* RAM speed is often expressed in

nanoseconds or megahertz

* SDRAM is fast and relatively inexpensive

—DDR

* RDRAM is more expensive, and usually

found in high-performance workstations

Read-Only Memory

* ROM is a type of memory circuitry that holds

the computer's startup routine

— Permanent and non-volatile

*The ROM BIOS tells the computer how to

access the hard disk, find the operating

system, and load it into RAM

* More permanent than

RAM, and less

permanent than ROM

installed Memory Memory Bank 0 Memory Bank 1 Core Version BIOS Revision CPU Type

CPU Speed/FSB Cache RAM

[10:40:40]

[03/03/2007]

[English {US]]

[1.44Mb 3.5'1 [Maxtor 38916H8 - [PMỊ ] [None]

[LG CD-RW CED-8080B- [SM] | [LG DVD-ROM DRD-0120H]

512 MB/233 MHz

512 MB SDRAM Not Installed 4.06 4.04 12/07/06

Storage Basics

* A storage medium contains data

* A storage device records and retrieves data

from a storage medium

— Data gets copied from a storage device into RAM, where it waits to be processed

— Processed data is held temporarily in RAM before it is copied to a storage medium

Magnetic Disk and Tape Technology

* Magnetic storage stores data by magnetizing

microscopic particles on the disk or tape

Hard disk platters and read-

write heads are sealed inside

_ the drive case or cartridge to

screen out dust and other contaminants.

Magnetic Disk and

lape Technology

* A controller positions the disk and read-write

heads to locate data

CD and DVD Technology

At,

* Optical storage stores data as microscopic

light and dark spots on the disk surface

— CD and DVD storage technologies

CD and DVD Technology

* Today’s DVD drives typically have 16X

speeds for a data transfer rate of 177.28

CD and DVD Technology

Play Audio CDs

Solid State Storage

* Solid state storage technology stores data in

an erasable, rewritable circuitry

* Non-volatile

* Card reader may be required

to read data on solid state

storage

Solid State Storage

A USB flash drive is a

ortable storage d that plugs directly

computer's USB p

using a built-in

connector

evice into a

ort

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SECTION I

NpUbAnG OULpUL Devices

* Basic Input Devices

Display Devices

* Viewable image size — bigger is better

* Dot pitch — smaller is better

* Refresh rate — higher

SVGA 800 x 600

* Color depth — how many XGA 1024 x 768

colors can be displayed ” oe

* Resolution WUXGA 1920 x 1200

— VGA, SVGA, XGA, SXGA, UXGA, and WUXGA

Display Devices

* Graphics circuitry generates the signals for

displaying an image on the screen

* An ink-jet printer has a nozzle-like print head

that sprays ink onto paper

* A laser printer works like a photocopier

Printers

Laser printers are a popular technology when high-volume output or good-quality printouts

Printers

* Dot matrix printers produce characters and

graphics by using a grid of fine wires

— The wires strike a ribbon and the paper

2 PXA\ Vi, Wig

paper and, therefore, can print multipart carbon forms

Characters are

= pattern of dots : created as the

inked ribbon

Printers

* Printer features

— Resolution — Duplex capability — 1 or 2

— Print speed (per minute) sides

Laser (B&W) 2400 dpi 10-20 ppm 150,000 ppm 2-4ýipage 8-120 MB

Installing Peripheral Devices

* The data bus moves data within the

or by touching both hands to a metal object

* Peripheral device may

include the Plug and Play feature, or require

Connects to USB port, which sends data

over a single data line and can support

up to 127 devices USB-1 carries data at speeds up to 12,000 Kbps; USB-2, at 480,000 Kbps

Connects to the FireWire port, which sends data at 400,000 Kbps

Connects to the video port

DEVICES

Modem, keyboard, joystick, scanner, mouse, external hard disk drive, MP3 player, digital camera

Video camera, DVD player

Monitor

-

Mana Wale Se CUNT,

* Surge Protection and Battery Backup

* Basic Maintenance

* Troubleshooting and Repair

Chapter 2: Computer Hardware

_ Surge Protection

and Battery Backup

* A power surge is a sudden increase or spike in

electrical energy, affecting the current that flows to electrical outlets

* A surge strip is a device that contains electrical

outlets protected by circuitry that blocks surges and

spikes

* A UPS is a device that not only provides surge

protection, but also furnishes your computer with battery backup power during a power outage

2 Basic Maintenance

* Computer component failures can be caused

by manufacturing defects and other circumstances beyond your control

* Keep the keyboard clean

* Clean your computer screen on a regular

basis

* Keep the area clean around your computer

* Make sure fans are free of dust

Carefully use a Q-tip and a can

of compressed air or a vacuum cleaner to remove dust and debris from your keyboard

Troubleshooting and Repair

* There are several telltale signs that your

computer is in trouble

— Failure to power up

— Loud beep

— Blue screen of death

* Help and Support Center

* Safe Mode

Troubleshooting and Repair

* Stay calm and don't jump to any conclusions until you've thought everything through

* Write down all error messages and any other information that goes with them

* Make sure all components are plugged in and that there are no loose cables For example, if your monitor's

cable is loose, the indicator light will be off and your screen will be blank

* If you can, try to duplicate the problem by going through the same steps that led you to it

* Look for troubleshooting and repair tips in your user's manual, your vendor's Web site, or even through a

search engine If you search the Internet by typing in the error message number or keywords in the error

message, you might discover that at least one person has already found a solution to your problem

* Run your spyware and antivirus software Lurking viruses, worms, Trojan Horses, and spyware (discussed in

the next chapter), can cause strange and unexplainable occurrences in your computer system For example,

spyware Can cause your computer to keep displaying a pop-up ad no matter how you try to close it

* Asimple reboot of your computer might clear up the problem Windows always requires a reboot when it dis-

plays the blue screen of death on your screen However, a more serious problem underlying a BSoD will not

be resolved with a reboot To reboot a PC, hold down the Ctrl, Alt, and Del keys at the same time When the

Task Manager window appears, hold down the Ctrl, Alt, and Del keys once again.

NEW PERSPECTIVES

COMPUTER CONCEPTS

Chapter 2 Complete

Computer Hardware