Types of Processor

Question 1

What is a multicore processor?

Answer 1

A CPU has two or more processing units that can independently Fetch Decode and Execute instructions at the same time

Question 2

What is parallel Processing

Answer 2

Can take advantage of a multicore processor, using specialised software we can distribute workload from the same problem to speed up its execution

Question 3

What is a co-processor?

Answer 3

A additional processor that the CPU can offload specific tasks to

Question 4

What is RISC

Answer 4

Reduced Instruction Set Computers have;

• Small instruction sets
• Less complex hardware - therefore cheaper to produce, requires less cooling, uses less power.
• 1 instruction takes 1 FDE cycle (can use pipelining)
• One complex task will take many lines of source code
• Compiler needs to be complex to convert source code into RISC machine code.
• Suitable for smartphones, any small embedded devices

Question 5

What is CISC

Answer 5

Complex instruction Set Computers have;

• A large instruction set
• Very complex hardware - more expensive to produce, requires cooling and uses more power
• 1 instruction will take many FDE cycles to complete (no pipelining )
• One complex task can be completed with one line of source code
• Compiler doesn’t need to be too complex as CISC instructions are similar to machine code.
• Suitable for desktop computers.

Question 6

What are the pros and cons of RISC

Answer 6

• Few instructions available
• low power (Suitable for mobile devices)
• one instruction - 1 FDE (allows pipelining)

Question 7

What are the pros and cons of CISC

Answer 7

• Many instruction available
• Uses more power (not suitable for portable devices)
• one instruction = many FDE cycles

Question 8

What are the 3 types of CPU

Answer 8

Von Naumann, Harvard and Contemporary

Question 9

What is Von Neumann Archetecture

Answer 9

Instructions and data are stored together in the same memory. Requires a single set of busses and a single CU. Von Neumann bottleneck, when we have to fetch twice

Question 10

What is a Harvard CPU

Answer 10

Instructions and data are stored in separate memories. Each accessed via separate busses. Requires a more complex CU. Can fetch quicker that Von Neumann as can Fetch instructions and associated data at the same time. NOT memory efficient

Question 11

What is a contemporary CPU

Answer 11

Might use Harvard for cache memory- to store frequently used instructions and data in separate areas of cache

Question 12

What is a GPU

Answer 12

(Graphical Processing Unit) Has many many processing cores. They are specialist co-processors designed for rendering graphics, but can be used also to complete parallel processing tasks where the same instruction is repeated for items of data.

Rendering graphics requires BULK processing of similar instructions across many pixels on the screen