SC ICT CertificationLevel 1

SC ICT CertificationLevel 1

03 Computer Hardware

By Ross Parker

WHY DO I CARE?03.1

Mysterious Magical Stuff

• Do you treat your computer like a “black box”?

• Why should I care what it is doing inside?

4 Reasons• Purchasing

– Understand what you are buying

• Performance– Know why your computer is running slow

• Power– Persuade your boss as to why you need a

new or upgraded computer!

• Peace-of-mind– Understand what is normal and what is not

THE BASICS03.2

What is a Computer?

Source: Lawrence Livermore National Laboratory

What is a Computer?

Source: Wikimedia Commons

What is a Computer?

Source: Wikimedia Commons

What is a Computer?

Source: Wikimedia Commons

What is a Computer?

Source: Wikimedia Commons

What is a Computer?

• wikipedia.org: “a computer is a machine that manipulates data according to a list of instructions.”

• techterms.com: “technically, a computer is a programmable machine”

• merriam-webster.com: “a programmable usually electronic device that can store, retrieve, and process data”

How a Computer Works“The Fundamental Idea”

wikipedia.org: “a computer is a machine that manipulates data according to a list of instructions.”

I / OI / O

How a Computer Works“The Fundamental Idea”

DiskStorage

DiskStorage

KeyboardMouseCD-ROMVoiceData Collection DevicesTouch and beyond

DiskStorage

MonitorPrinterSpeakers

DiskStorage

Hard DriveCD-ROM - WritableUSB

DiskStorage

Storage Capacity

DiskStorage

120 to 250GB(Gigabytes)

A Little More on Disk Storage• How much do you need?

• Buy the biggest that you can afford!

• 100 Gigabytes: all the academic journals on the shelves of a single library floor

• 10 Terabytes: all printed collections of U.S. Library of Congress

• 5 Exabytes: All words ever spoken by human beings

What Does This Storage Mean for You?

1TB (Terabyte) Hard Drive

•781,250 pictures

•1,250 hours of video

INSIDE THE COMPUTER03.3

What Makes a Computer

Motherboard

CPU

GigaHertz (GHz)2.00GHz

2 Billion Calculations per Second!!!

Memory - RAM

• Typical RAM size for 2008: 2GB• Good RAM size for 2008: 4GB• Outstanding RAM size for 2008: 16GB

What Makes a Computer?• Motherboard – connects together and coordinates other components.

• CPU – processes information according to stored instructions. The heart of the beast!

• Internal Storage – persistent instruction and data storage. Usually a hard disk.

• Memory– temporary instruction and data storage. Usually RAM.

• Removable media devices

• I/O– Keyboard, mouse, webcam– Display, speakers– Network

• Power supply

Slowness• Hardware

– Older, slower processor– Insufficient RAM– Slow hard drive– Hard drive almost at capacity– Network issues

• Software– Demanding operating system & applications– Excessive multi-tasking– Malicious software

PLAYTIME!03.4

The Messy, Real-World ViewCase

Hard drive(hidden)

RAM

CPU

Power supply

Cable nest

Motherboard

Optical Drive

(on top)

InternalStorage(hidden)

Get Stuck In• There is a computer for you to play with.• Can you?:

– Connect up the external cables on the back panel.– Open the case.– Ground yourself on the power supply.

• Discharge dangerous static.• Computer should be off, and plugged in to a socket that is

switched off.– Identify:

• The motherboard• CPU• Internal storage• Memory• Power supply

– Reseat the RAM– Remove and replace the internal storage

cabling on both ends.

OUTRODUCTION03.5

Measures

• CPU: MHz, GHz, FlOps

• Memory: kB, MB, GB, TB

• Network: kb/s, Mb/s

• Screen Resolution: px

• Hard drive: rpm

• Optical drive: YYx

Summary

• Extreme complexity

• Understandable by most

• Grasp what you are buying

• Basic knowledge of problems

• Understanding of that mysterious magical stuff

Thank You

Licensing• All original work used here is licensed under the Creative Commons Attribution-Share

Alike 3.0 Unported license. For more details please look at http://creativecommons.org/licenses/by-sa/3.0/.

• This license has been chosen to permit a high degree of sharing, whilst protecting the author’s control as to how the content is used.

• Please respect this license and use accordingly!• Recycled and borrowed works from other sources are used under appropriate

licenses, which are not affected by this license. The original source is always given. • All original work created by Ross Parker (Sha Tin College, English Schools

Foundation, Hong Kong), except where specified.