MODULE 3 ITC

system unit

system unit

case that contains electronic components of the computer used to process data

motherboard

main circuit board of the system unit

chip

contains integrated circuits

processor/central processing unit

interprets and carries out the basic instructions that operate a computer

control unit

component of the processor that directs and coordinates most of the operations in the computer

arithmetic logic unit (ALU)

arithmetic, comparison, and other operations

clock speed

pace of the system clock

gigahertz (GHz)

clock speed is measured in ____

system clock

controls the timing of all computer operations

Memory

consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data

1 thousand

1 million

1 billion

1 trillion

1 kb = ____ b

1 mb = ____ b

1 gb = ____ b

1 tb = ____ b

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

Dynamic RAM

is a type of random-access memory that stores each bit of data in a separate capacitor within an integrated circuit. The capacitor can be either charged or discharged

Static RAM

has three different states. It can be in: standby (the circuit is idle), reading (the data has been requested) and writing (updating the contents).

Magnetoresistive RAM

data in MRAM is not stored as electric charge or current flows, but by magnetic storage elements.

Singe Data rate RAM

SDRAM

Double Data Rate Synchronous Dynamic RAM

• DDR SDRAM

• memory transfer data on both the rising and falling edges of the clock signal

• 400 MT/s

DDR2 SDRAM

• 8.5 GT/s; “dual channel mode”; memory installed in pairs

DDR3 SDRAM

• Operates at lower voltages; consuming less power

• 12.8 GT/s; dual and triple channel modes

RAM chips

usually reside on a memory module and are inserted into memory slots.

Memory cache

speeds the processes of the computer because it stores frequently used instructions and data

Read-only memory (ROM)

refers to memory chips storing permanent data and instructions

Flash memory

can be erased electronically and rewritten

hard disk drive (hdd)

a non-volatile storage device which stores digitally encoded data on rapidly rotating platters with magnetic surfaces.

Digital Video Disc (dvd)

• optical disc storage media format. Its main uses are video and data storage.

• same dimensions as compact discs (CDs) but store more than six times as much data.

Blu-ray Disc

optical disc storage medium to supersede the standard DVD format. Its main uses are for storing PlayStation 3 games, high definition video and data storage with up to 50GB per disc. The disc has the same physical dimensions as standard DVDs and CDs.

USB flash drive

• consists of a NAND-type flash memory data storage device integrated with a USB (Universal Serial Bus) interface.

• typically removable and rewritable, and most

• weigh less than an ounce (30 g)

memory card/flash memory card

• solid-state electronic flash memory data storage device capable of storing digital contents

• mainly used with digital cameras, handheld and Mobile computers, mobile phones, etc.

keyboard

used to type data into the computer

Pointing devices

move some object on the screen and can do some action

scanner

allows you to scan documents, pictures or graphics and view them on the computer. It converts image into dots that the computer can understand

Digital cameras

used to take electronic pictures of an object

Microphones

used to put sound into a computer. Today, commands can also be given to computer using your voice.

Monitors

shows the processed information on screen. It displays soft copy of the information. When the device is turned off the information goes away

Printers

produces a hard copy of the information.