Computing Hardware

Computing Hardware

1. CPU

   • The CPU carried out all the processed and functions in computer.
   • When the computer is switched, the CPU automatically begins the endless fetch, decide and execute cycle.
   • The program the CPU needs to process are stored in the main memory.
   • The CPU fetches the next instruction it needs to process, decodes it to find out what processing to do and executes it.
   • Processor speed is measured in gigahertz (GHz) (billions of cycles per second). This is the number of fetch-execute cycles a processor can perform per second.
   • Factors that influence performance include: Amount of Cache available and number of processor cores.

2. Cache Memory

   • Cache memory is special high speed memory used by a computer.
   • Data that is in use is transferred into the cache memory to make access to it faster.
   • Similarities with RAM: Both volatile (lose all data when power is switch off); both used as main memory (primary memory), cache is used to store data waiting to be processed.
   • Differences with RAM: Cache memory is faster, works at the same speed as the CPU.Is a lot smaller (MBs rather than GBs).

3. Input and Output Devices

   • Input device - Used to enter data into a computer for processing.
   • Output device - Used to show the results of data that has been processed by a computer system.
   • Peripheral - Is any hardware device which connects to the computer and controlled by the CPU.