Computer Hardware Pt.1

Computer Hardware Pt.1

1. Central Processing Unit (CPU)

   • The Purpose of the CPU is to process data.
     • FETCH: (1st step) fetch data and instructions from main memory then store them in own internal temporary memory areas.
       • DECODE: (2nd step) CPU has to decode (make sense of) the instruction that it has just fetched.
         • EXECUTE: (3rd step) Carry out the data (This is when the processing takes place).
   • Cache
     • Used to temporarily hold instructions/commands.
     • Small amount of memory which is part of a CPU.
     • The larger the cache size, the better the performance as it is able to store more data locally.
   • No. Cores
     • CPUs with multiple cores have the power to run multiple programs at the same time.
     • CPUs can contain one or more processing units - each unit called a core.
   • Clock Speed
     • Clock speed indicates how fast the CPU can run.
     • The CPU clock speed is measured in cycles per second.
     • The speed of the clock determines basic performance of the CPU - the faster it goes, the more powerful the computer is.

2. Memory

   • ROM: Read only memory
     • Non-volatile memory.
     • Stores the instructions which the computer uses when it 'boots up' the BIOS.
     • ROM retains data even without power.
   • RAM: Random access memory.
     • Volatile Memory.
     • Anything stored within this will be lost as soon as the power is cut.