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Chapter 2

This chapter delves into the various components and standards that define modern computer hardware, focusing on input, output, and storage devices, along with expansion capabilities.

Chapter 2

Chapter 2: Hardware Designed to Meet the Need

Selecting and Purchasing a Computer

Select Add-ons
Choose model
Choose manufacturer
Choose platform
Choose computer type
Determine your needs

Main topic

Input, Output, and Expansion

Expansion
eSATA
Firewire

Also known as IEEE 1394 or iLink

Firewire 800

New Firewire standard

Firewire 400

About the same speed as USB 2.0

USB

USB 3.0

New USB standard and it is about 10 times faster than USB 2.0

USB 2.0

Most popular today, up to 480 Gb/s

USB 1.1

USB 1.0

Output device

An output device allows you to observe the results of computer processing with one or more of your senses.

Sound Systems
Printers and Plotters
LCD
Input device

An input device assists in capturing and entering raw data into the computer system.

Scanner
Webcam
Gamepad
Microhphone
Stylus
Trackball
Mouse
Keyboard
Secondary Storage

used to store data more permanently without the need for electricity.

Solid State storage

Solid state storage devices store data using

transistors. Also store the data without the need for electricity.

USB Flash Drives

Also known as USB thumb drive

Convenient, portable, high-capacity storage

Flash memory card

Keeps its memory when the power is shut down

Optical storage

Uses optical laser to burn pits into the surface of

a highly reflective disk

Blu-laser Disk

Able to read smaller pits, which allows for greater

capacity

DVD

Digital video disk read-only memory(DVD-ROM): stores over 4.7GB of data

CD

Compact disk read-only memory(CD-ROM): Optical media that stores up to 700 MB of data.

Magnetic storage

Magnetic storage devices use the magnetic properties of iron oxide particles to store bits and bytes more permanently than RAM.

Microdrives

Tiny hard drives that store data on a small disk

High-capacity Disks & Floppy Disks (outdated)

Portable, low-capacity, direct storage medium (out-dated)

Magnetic Tape

Hard Disk Drives

System Storage

System storage is storage that is used by a computer system for standard operations.

CMOS

- Semi-permanent storage for information that may

change

- Able to keep accurate time and date even when

computer is shut down

ROM

Read-only memory (ROM) Provides permanent storage for data and instructions.

non-volatile

Video RAM

Graphics memory, sometimes called video RAM or VRAM, is used to store image data for a computer display in order to speed the processing and display of video images.

Cache

RAM stands for Random Access Memory.

Also known as memory or primary (main) storage.

random access

Random access (sometimes called direct access) is the ability to access an arbitrary element of a sequence in equal time. The opposite is sequential access, where a remote element takes longer time to access.

volatile

requires power to maintain the stored information

Integrated Circuits and Processing

Motherboard

Primary circuit board of a computing device. CPU, system storage, system bus are on the motherboard.

Expansion Slots
System Bus

The system bus connects the CPU to the chipset, and through it to RAM and other components on the motherboard.

RAM

Random access memory(RAM). Temporary, or volatile, memory that stores bytes of data and program instructions for the processor to access.

CPU

Central processing unit(CPU), it is a group of integrated circuits that perform processing.

Machine Cycle

store

execute

decode

fetch

CPU performance factors

Key Terms

Millions of instructions per second (MIPS)

Amount of time it takes to execute an instruction

Floating-point operations per second (FLOPS)

-More precise than MIPS

-Gigaflop, teraflop

System clock

Produces a series of electronic pulses at a

predetermined rate called clock speed

Front Side Bus

FSB is now replaced by QPI (QuickPath Interconnect) in Core i CPU.

Architecture

Wordlength

Number of bits that a CPU can process at once

Cache memory

High-speed memory a processor can access more

quickly than RAM

Processor numbers

Used to market processors instead of clock speed

Clock speed

Measured in megahertz (MHz) or gigahertz (GHz)

Key components

L1 (and L2) cache

Recent CPU contains L1 and L2 cache.

Registers

Registers hold the bytes currently being

processed.

Control Unit

The control unit sequentially accesses and decodes program instructions, decodes them, and coordinates flow of data in and out of ALU.

ALU

Arithmetic/logic unit (ALU), it contains the circuitry to carry out instructions, such as mathematical and logical operations.

Integrated Circuit

also called chips. It is used to store and process bits and bytes in today's computers.

Transistor

Composed of semiconducting material that opens or

closes a circuit.

Computer Key components
Operating System
Security
Networking
Video
Removable Storage
Storage

Storage is the ability to maintain data within the

system permanently or temporarily.

Memory
Processor

also known as CPU

The Digital Revolution

Digital Convergence

Digital convergence is the trend to merge multiple digital services into one device.

Binary number system
ASCII

American Standard Code for Information

Interchange(ASCII). Code representing keyboard text characters

Byte

Eight bits is a byte – the standard grouping in digital electronics.

Bit

Bits aren’t really 1’s and 0’s, they are devices that can be set to one of two states.