RISC / CISC & SISD / SIMD / MIMD

Question 1

RISC

Answer 1

RISC (Reduced Instruction Set Computing)
• Only one value fetched/       stored per instruction cycle
• Less Power Required
• Used in smaller devices
(Smartphones)
• Generates less heat - requires less
cooling methods

Question 2

CISC

Answer 2

CISC (Complex Instruction Set Computing)
• One instruction can complete an entire sequence - more complex
• Higher Power Consumption
• Powerful
• Generates more heat

Question 3

SISD

Answer 3

Single Instruction, Single Datastream
Single Core CPUs
NB:
• No parallelism
• Single CU, fetches single instruction

Question 4

SIMD

Answer 4

Single Instruction, Multiple Datastreams GPUs
NB:
• One instruction preformed on many data-streams
• Naturally parallelized operations
• Examples: Fractal Rendering, Graphics Processing (hence GPUs) -
each pixel is independent

Question 5

MIMD

Answer 5

Multiple Instructions, Multiple Datastreams Multi-core CPUs
NB:
• Multiple autonomous processors simultaneously executing different instructions on different data
• Uses either one shared memory space or a distributed memory space.