GSCE :Section 1: Components of a Computer System

Question 1

What is a computer?

Answer 1

A computer is a machine that processes data

Question 2

What is the purpose of a computer?

Answer 2

• To take data
• Process it
• Then output it

Question 3

What does a computer system include?

Answer 3

• Hardware
• Software

Question 4

What is Hardware?

Answer 4

The physical stuff that makes up the computer e.g. CPU, motherboard

Question 5

What is Software?

Answer 5

The programs or applications that computer system runs e.g. an operating system

Question 6

What are embedded systems?

Answer 6

They are computers that are inside a larger system e.g. dishwasher

Question 7

What is inside a typical desktop computer?

Answer 7

• Motherboard
• Hard disk drive
• Graphics Card
• CPU

These are only a couple of examples

Question 8

What is the purpose of the CPU?

Answer 8

It processes all the data and instructions to make a system work.

Question 9

What is the purpose of the GPU?

Answer 9

It handles graphics and images + relieves processing load on CPU

Question 10

What are some of the factors that affect the CPU?

Answer 10

• Clock speed
• Cache size
• Number of cores

Question 11

What are the CPU’s main 3 parts?

Answer 11

• The Control Unit (CU)
• The Arithmetic Logic Unit (ALU)
• The Cache

Question 12

What does the Control Unit (CU) do?

Answer 12

It executes instructions and controls the flow of data in the CPU

Question 13

What does the Arithmetic Logic Unit do (ALU)?

Answer 13

• Does all the calculations
• Performs logic operations (AND, OR , NOT)
• Performs binary shifts

Question 14

What does the Cache do?

Answer 14

• Stores regularly used data so the CPU can access it quickly
• It has low capacity + is expensive
• Has very fast memory

Question 15

What does the Von Neumann architecture describe?

Answer 15

A system where the CPU runs programs stored in memory

Question 16

What are the two types of registers?

Answer 16

• Memory Address Register (MAR)
• Memory Data Register (MDR)

Question 17

What does the Program Counter do?

Answer 17

Holds the address of the instruction for each cycle

Question 18

What does the Accumulator do?

Answer 18

Stores results of calculation in the ALU

Question 19

What does the MAR do?

Answer 19

Hold the memory address ABOUT to be used by the CPU

Question 20

What does the MDR do?

Answer 20

Holds the ACTUAL data/ instruction used by the CPU

Question 21

What is the Fetch –> Decode –> Execute cycle?

Answer 21

Fetch:
- Memory address is copied from the program counter to the MAR
- Cppy the instruction stored in the MAR address to the MDR
- Increments the program counter to point to the address of the next instruction

Decode:
- Instruction from the MDR is decoded by the CU
- The CU prepares the next step by loading the values into the MAR or MDR

Execute:
- The instruction is performed

Question 22

What is RAM?

Answer 22

Random Access Memory

Question 23

What is ROM?

Answer 23

Read Only Memory

Question 24

What is virtual memory?

Answer 24

It’s secondary storage used by the RAM

Question 25

Factors of RAM:

Answer 25

• High speed volatile memory (temporary
  memory)
  -Slower than the CPU cache
• Faster than secondary storage

Power off = Data is lost

Question 26

Factors of ROM:

Answer 26

• Non volatile
  -Contains all the instructions needed for the computer to boot up

Question 27

When is Virtual Memory used?

Answer 27

When the RAM is full- it uses secondary storage as a temporary RAM

Question 28

Factors that affect the CPU:

Answer 28

• Clock speed
• Cache Size
• Number of Cores

Question 29

What is clock-speed?

Answer 29

The number of instructions a processor can carry out per second

Question 30

What is number of cores + its effects ?

Answer 30

The more number of cores the CPU has it can carry out more instructions at once

More cores - Faster processing

Question 31

What is the affects of the cache size?

Answer 31

A larger cache gives the CPU faster access to more data

Question 32

What is secondary storage?

Answer 32

It’s where all the data including the programs are stored when they are not being used

Question 33

Give at least 3 advantages about Hard Disk Drive (HDD)

Answer 33

• Longer Life Span than SSD
• Large storage capacity
• Lower cost than SSD

Question 34

Give at least 3 disadvantages about Hard Disk Drive (HDD)

Answer 34

• Has moving parts
• Noisy
• Not Shock Proof

Question 35

Give at 3 advantages of about Solid State Drive (SDD)

Answer 35

• No moving parts
• More robust than HDD
• Faster than HDD

Question 36

Give at 3 disadvantages of about Solid State Drive (SDD)

Answer 36

• More expensive than HDD
• Lifespan of SDD is less than HDD

Question 37

Give some examples of Flash memory

Answer 37

• USB memory sticks
• Memory Cards

Question 38

Give 3 advantages about Optical Storage and state some examples

Answer 38

• Cheap
• Portable
• Robust

e.g. CDs, DVDs

Question 39

Give 3 disadvantages about Optical Storage and state some examples

Answer 39

• Not scratch- resistant
• Low capacity
• Very slow to write to

Question 40

Give at 3 advantages about Magnetic Tape

Answer 40

• Used for back ups
• Large Capacity
• Low Cost

Question 41

Give a disadvantage about Magnetic Tape

Answer 41

• Slow