How to Build a PC - IGN: "What to Buy
The most basic parts you’ll need are as follows:
Central Processing Unit (CPU)
(This is the "brain" that tells your system what to do.)
(This keeps your CPU from overheating and shutting off.)
(This is the circuit board that relays all the commands between the parts—like the hub of a wheel that all the spokes connect to.)
Random-Access Memory (RAM)
(Your computer uses this form of super-fast memory to hold the data it’s currently working on—like a game’s textures.)
(The graphics processor inside this crunches polygons and tells your monitor what to display.)
Solid State Drive (SSD) and/or Hard Disk Drive (HDD)
(You store data—such as games, applications, documents, and other files—here for retrieval.)
(This houses all the parts and keeps dust at bay.)
Power Supply Unit
(This provides electricity to the machine.)"
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