The Central Processing Unit Processor and Main Memory
Dec 22, 2015
The Central Processing Unit
Processor and Main Memory
Learning Intentions• We are learning to:• State the function of the processor• Describe the differences between RAM and
ROM• Make comparisons between computer systems
using processor speed and main memory size.• State the function of graphics and sound cards.
The Computer System
INPUT OUTPUT
BACKING
STORAGE
Processor
MAIN MEMORY
Processor and Main Memory
• Processor - Deals with all the movement of data and the calculations that need to be carried out.
• Main Memory-Used to store programs and data
Processor
Main Memory
Makes of processor
Clock speedA5 processor (IPAD)
Intel Core i7
• Clock speeds are a measure of how powerful a processor is.
• 1 Megahertz (1 MHz) = 1 million pulses per second
• 1 Gigahertz (1 GHz) = 1000 million pulses per second
800MHz
3.2 GHz
Clock speed examples
Type System Processor Speed
Smartphone BlackBerry Bold 9780
624 MHz Slowest
Tablet Samsung Galaxy Tablet 2
1 GHz
Laptop Asus Ultrabook 1.6 GHz
Desktop HP Desktop PC 3.4 GHz Fastest
The Main Memory
• The main memory can be either RAM or ROM.
• Random Access Memory is the working space of the computer.
• It holds all the programs and data you are currently using.
• When you are using MS Word it has been loaded from your computer’s hard disk into RAM.
• The unsaved work you have typed so far is also held in RAM.
Read Only Memory
• Read Only Memory is used by the computer to store data permanently.
• In computer systems ROM is used to store the Operating System of your computer.
• Stores the programs that run MP3 players, Washing machines, Central Heating system and other devices in your home
• It is very difficult to change the data held in ROM
RAM vs ROM
Random Access Memory Read Only Memory
Read and Write Read Only
Data can be changed Data CANNOT be changed
Data is lost when power is switched off - Temporary
Data is kept when power is switched off - Permanent
Holds all the data and programs currently in use
Holds instructions the computer and devices need to carry out their function
Complete the table in your jotterComputer
SystemProcessor Speed Main Memory
(RAM)Samsung Galaxy S smartphone
1 GHz 512 Mb
Yarvik Zania 10 TabletAcer Apsire UltrabookASUS Essentio Desktop PC
Using www.pcworld.co.uk
AnswersComputer
SystemProcessor Speed Main Memory
(RAM)Samsung Galaxy S smartphone
1 GHz 512 Mb
Yarvik Zania 10 Tablet
1.2 GHz 1 Gb
Acer Apsire Ultrabook
1.7 GHz 4 Gb
ASUS Essentio Desktop PC
3.3 GHz 4 Gb
Graphics Card• Specialised piece of
hardware used to process the images and videos you see on your screen.
• They have their own processor and memory.
• The CPU then has the time to get on with processing other data.
• The best graphics cards allow your games to run smoothly.
Graphics Card- In Your JotterGraphics Card Processor
speed (frequency)
Memory Price
PNY Ge Force 8400
ASUS AMD Radeon HD6770 ASUS NVIDIA Geforce GTX 680 Using www.pcworld.co.uk
AnswersGraphics Card Processor
speed (frequency)
Memory Price
PNY Ge Force 8400
520 MHz 512 Mb £ 19.97
ASUS AMD Radeon HD6770
850 MHz 1 Gb £99.99
ASUS NVIDIA Geforce GTX 680
1201 MHz 2048 Mb (2Gb)
£468.00
Sound Cards
• The sound card is used to capture and output audio data.
• They improve the quality of sound output from games and multimedia.
• Sample Rate: A measure of the quality of the sound that has been captured. Measure in KHz
Sound Card shopping- In your jotter
Graphics Card Test Frequency(Sample Rate)
Price
CREATIVE Sound Blaster X-Fi Xtreme ASUS Xonar HDAV1.3
Using www.pcworld.co.uk
Answers
Graphics Card Test Frequency(Sample Rate)
Price
CREATIVE Sound Blaster X-Fi Xtreme
Up to 96 kHz £39.97
ASUS Xonar HDAV1.3
192 kHz £129.97