An Introduction to PC Components

If you are thinking about building or repairing computer equipment, there are only six main classes of component that you need to know about:

CPU (Central Processing Unit): this is the chip that processes the instructions: it is sometimes likened to the brain of the PC
Motherboard: this is the main circuit board that all the other components slot into. This can be likened to the nervous system - enabling all the components to communicate with each other
RAM (Random Access Memory): this is the temporary storage area used by the computer whilst it is operating to hold both instructions and data. As anything in RAM is lost when the computer is switched off, this can be likened to our short-term memory
Drives: these are used for permanent storage or for loading in programs and data. As anything stored on a drive is retained when the power is removed, this can be likened to our long-term memory
Power Supply (PSU): this is the unit that takes the AC mains power and transforms it into reliable DC power for the PC components. This can be likened to the heart of the computer - supplying vital life-force to all components
Case: this is the housing (-normally a combination of metal inner cage and plastic outer) that the other components are mounted inside. This can be likened to the skeleton of the computer, both protecting and holding everything together
Expansion Cards: these are smaller daughterboards that plug directly into the expansion slots on the motherboard and give the PC some additional capability. You can think of these as training/education in that it extends the capabilities of the computer

If you are thinking about building or repairing computer equipment, there are only six main classes of component that you need to know about

Most home PCs will normally contain:

A single CPU: although there are multi-CPU machines, home machines currently all have a single chip (-albeit with multiple Cores)
A single Motherboard: the Motherboard will have a single slot that allows a chip from a single CPU family, plus one or more RAM slots
One or more RAM DIMMs: the maximum amount of RAM will be determined by the number of slots in the Motherboard
One or more Drives: the maximum amount of drives possible will be determined by the number of data connectors on the Motherboard and the number of power connectors from the PSU
A single PSU: this should generate enough power for all components attached to the system
A single Case: this should be large enough to accommodate all the other (internal) components