1.1 System Architecture Flashcards
CPU
Responsible for carrying out all the instructions.
Number of institutions that can be performed in 1 second
GHz
CU
Control unit
- decides which instruction to carry out and fetches it and executes it
- executes instructions
ALU
Performs calculation, makes logical decisions. Gateway between CPU and rest of computer.
Register contains…
PC MDR MAR CIR ACC
Fetch- Decode- Execute cycle
How the CPU processes all of the data and institutions
Cache
- Very fast memory within the CPU
- Slower than register but faster than RAM
- Stores data and instructions that are used regularly so CPU can access it quickly
Three main factors that effect the performance of the CPU
- Clock speed
- Number of cores
- Cache size
1 hertz = __ pulses per second
1
1 Megahertz=____pulses per second
1000,000
Dangers of over clocking include
- data can get corrupted
- overheating
How many processing units can a CPU contain ?
- One or more (dual core, quad core)
- Each unit is called a core
What does a core contain
ALU, control unit and registers
What happens if a computer has too little RAM?
It may run slowly due to having to use virtual memory
What does having lots of RAM allow you to do?
-You will be able to run more programs at the same time and also run more memory intensive programs.
GPU
- Graphics processing unit
- Specialises in processing graphics and images
The 2 parts of a computer instruction
Opcode- operation that needs to be performed
Address (location) in memory the data for the instruction can be found
What does each instruction go through
Fetch, decode and execute
Registers
small areas of memory
PC
Program counter
MAR
Memory address register
MDR
Memory data register
ACC
Accumulator
CIR
Current instruction register
