Chapter 4

Well this its the last class before a long weekend ahead.Selamat Hari Raya Aidiladha to you and your family Miss !!!

System Unit Components :~

*Differentiate among various styles of system units on desktop computers, notebook computers, and mobile devices
*Identify chips, adapter cards, and other components of a motherboard
*Describe the control unit and arithmetic logic unit components of a processor, and explain the four steps in a machine cycle
*Identify characteristics of various personal computer processors on the market today, and describe the ways processors are cooled
*Define a bit and describe how a series of bits represents data
*Explain how program instructions transfer in and out of memory

*Differentiate among the various types of memory

*Describe the purpose and types of expansion slots and adapter cards, and differentiate among slots for various removable flash memory devices

*Differentiate between a port and a connector, and explain the differences among a USB port, *FireWire port, Bluetooth port, SCSI port, eSATA port, IrDA port, serial port, and MIDI port

*Describe the types of buses in a computer

*Explain the purpose of a power supply and describe how it keeps cool

*Understand how to clean a system unit on a computer or mobile device


The System Unit :~ 

The system unit is a case that contains electronic components of the computer used to process data

The inside of the system unit on a desktop personal computer includes : 

*Drive bay(s)
*Power supply
*Sound card
*Video card
*Processor

*Memory

The motherboard is the main circuit board of the system unit 

~a computer chip contains integrated circuits.

Processor :~

The processor, also called the central processing unit (CPU), interprets and carries out the basic instructions that operate a computer

~Contain a control unit and an arithmetic logic unit (ALU)

 

There are many types of Processors,A processor chip generates heat that could cause the chip to burning up.Therefore requiring additional cooling with :~

*Heat sinks
*Liquid cooling technology

Data Representation :~ 

Analog signals are continuous and vary in strength and quality

Digital signals are in one of two states: on or off

The binary system uses two unique digits (0 and 1)

A computer circuit represents the 0 or the 1 electronically by the presence or absence of an electrical charge

Memory :~ 

The system unit contains two types of memory :~

Volatile memory:~

*Loses its contents when power is turned off

*Example includes RAM

Nonvolatile memory:~

*Does not lose contents when power is removed

*Examples include ROM, flash memory, and CMOS

Expansion Slots and Adapter Cards:~

*An expansion slot is a socket on the motherboard that can hold an adapter card

*An adapter card enhances functions of a component of the system unit and/or provides connections to peripherals

~Sound card and video card.

Removable flash memory includes:
*Memory cards
*USB flash drives
*PC Cards/ExpressCard modules

Ports and Connectors:~

*A port is the point at which a peripheral attaches to or communicates with a system unit (sometimes referred to as a jack)

*A connector joins a cable to a port

Buses:~ 

*A bus allows the various devices both inside and attached to the system unit to communicate with each other

~Data bus

~Address bus

Common types of Expansion Buses include :~

*PCI bus
*PCI Express bus
*Accelerated Graphics Port
*USB and FireWire bus
*PC Card bus

Keeping Your Computer or Mobile Device Clean:~

*Clean your computer or mobile device once or twice a year

*Turn off and unplug your computer or mobile device before cleaning it

*Use compressed air to blow away dust

*Use an antistatic wipe to clean the exterior of the case and a cleaning solution and soft cloth to clean   the screen

Summary :~ 

*Components of the system unit

*How memory stores data, instructions, and information
*Sequence of operations that occur when a computer executes an instruction
*Comparison of various personal computer processors on the market today
*How to clean the exterior and interior of a system uni