Class5: Class5:

Computer HardwareComputer Hardware

Information Systems for Management

Outline

Information Systems for Management

• Electronic Data (bit, byte, larger sizes)

• Central Processing Unit (CPU)

• Main Memory (Primary Storage)

• Secondary Storage

• Computer Speed

• Input & Output Devices

• Moore's Law

Information Systems for Management

Electronic Data

Bit – electrical charge exists (meaning 1) or it does not (0)

Byte: String of bits (usually 8), representing one character

(letter, number)

1 Kilo Byte (KB) = 1000 Bytes

1 Mega Byte (MB) = 1,000,000 Bytes

1 Giga Byte (GB) = 1,000,000,000 Bytes

1 Terra Byte = 1012 Bytes

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Information Systems for Management

Central Processing Unit

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• CPU or processor is the key part of computer

Also important as support to CPU

Internal communications

Information Systems for Management

The CPU and MemoryCentral Processing Unit (Processor):

Arithmetic Logic Unit (ALU) Control unitComputer clock*

Main Memory (Storage), 2 parts:ROM (permanent) – programmed by manufacturerRAM (changeable) – memory used for your programs and operating system; PCs today – RAM size in Giga Bytes

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Information Systems for Management

Computer Speed

A CPU placed on a single miniature chip; basis of PC (personal computer)

Speed and performance factorsSpeed of Computer Clock Number of bits the computer can process at one time (Word length)Number of bits that can be moved at one time between the CPU, primary storage & other devices (Data Bus width)

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Information Systems for Management

Computer Speed - Examples

Name Manufacturer Word Length(bits)

Clock Speed(electrical cycles per

second)

Data Bus Width(bits)

Celeron Intel 32 500-2600 MHz 64

Pentium III Intel 32 500-1400 MHz 64

Pentium IV Intel 32 3.2 GHz* 64

Itanium II Intel 64 1.5 GHz 128

Opteron AMD 64 2.6 Ghz 128

MHz = millions of Hertz (measure of speed)GHz = billions of Hertz

Speed increase

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Information Systems for Management

Secondary Storage (Memory)

Long-term, non-changeable

Magnetic:Hard disk Flash drive other (floppy disk, tape)

Optical:CD-ROM (readable or readable and writeable - CD-R/CD-RW)DVD (same as CD-ROM, takes more data)

Secondary storage tech. keep developing and getting cheaper

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Information Systems for Management

Input Devices

Keyboard

Mouse

Touch screen

Readers/Scanners (Bar code reader; Magnetic Ink Recognition)

Radio Frequency Identification (RFID) Receiver*

Voice recognition

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Information Systems for Management

Output Devices

Monitor

PrinterNon impact (laser, inkjet; photo printer)Impact (dot matrix)

Plotter

Voice output (voice synthesizer)

Plotter

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Information Systems for Management

Moore’s “Law” *

Moore’s Law: In intervals of 2 years, the capacity of

computer memory, processing speed, the density of

components double.**

Gordon Moore, co-founder of Intel, mote this regularity in

mid-1960s.

Moore’s “Law” still valid. Important for hardware

purchasing.

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