YEAR 1 CO1 WEEK 7 TYPES OF PROCESSORS

Question 1

What does RISC stand for and what does it do?

Answer 1

Reduced Instruction Set Conputer.
Has more instructions, but reduces the number of cycles that instruction takes to perform.

Question 2

What does CISC stand for and what does it do?

Answer 2

Complex Instruction Set Computer.
Tries to reduce number of instructions program has by combining many simple instructions into single complex one.

Question 3

State the three types of Parallel Processing.

Answer 3

Pipelining
Array Processing
Multi-Core

Question 4

What is Pipelining?

Answer 4

This is where this cycle is staggered into multiple hardware processing paths within the CPU called a ‘pipeline’.

Question 5

What is Array Processing?

Answer 5

You can arrange data into an array (2D array).
Has a number of ALUs that allow all elements of an array to be processed at same time.

Question 6

What is meant by Multiple Processors?

Answer 6

Next level of Parallel Processing is to have multiple instructions acting upon multiple data sets.
Achieved by having number of CPUs applied to single problem, with each CPU carrying out part of overall problem.

Question 7

Disadvantages of Parallel Processing.

Answer 7

Only works on certain types of data which do not rely on previous operation.
Often expensive on hardware side.
Multiple processing blocks needed (applies to all three methods.)

Question 8

Advantages of Parallel Processing.

Answer 8

Makes maximum use of CPU (pipelining).
Faster when handling large amounts of data, each data set requiring the same processing (array + multi core method).
Not limited by bus transfer rate.

Question 9

What is a Co Processor?

Answer 9

Designed to carry out floating point calculations extremely fast and works with CPU on mother board.
When CPU has a task like this sent to Co processor and does something else until its done.

Question 10

State Advantages and Disadavantages of Co Processor.

Answer 10

Calculations done much faster.

More expensive, requires more motherboard space and takes more power.
Has limited range of function.

Question 11

What is a GPU and state its function.

Answer 11

A Graphics Processing Unit which is designed to handle graphics and video much faster than the CPU itself.
Has instruction sets which relate specifically to graphics processing.

Question 12

What happens when application makes intense use of graphics or video?

Answer 12

CPU sends these tasks to GPU and continues to process other tasks.
Many graphics tasks run in parallel di GPU issues single instruction act upon many pixels at same time.

Question 13

State issues with GPUs.

Answer 13

Graphics cards can be expensive.
Do not improve CPU performance on all tasks, only ones related to graphics and videos.
Uses alot of power which might mean computer needs to be fitted with a more powerful power supply.
As graphics cards use lots of power need cooling fan which can be very noisy.

Question 14

Give some features of CISC explained.

Answer 14

MUL 1045,1067
This reduces amount of work compiler has to do. As instructions very high level and requires little translation into machine code.
As instructions very short only small amount of RAM required.
Clock speed slightly slower as CPU has to do more work in single instruction.

Question 15

Give some features of RISC explained.

Answer 15

Complier has lot more work to do translating high level language into machine code.
More RAM needed to store machine code instructions.

Question 16

Give some comparisons between RISC and CISC.

Answer 16

CISC
Each instruction takes multiple cycles.
More transistors means more power consumed means more heat.
Less use of RAM.
Hardware more complex + larger in size.
RISC
Each instruction takes one cycle.
Less transistors so not as hot.
Heavy use of RAM.
Hardware simpler + smaller in size.