copy/paste from my lj

Someone who knows about computers, could you help a bit? So, I'm pondering buying a new motherboard, graphic card, processor and a FAN, because this one makes noise. Or it's the motherboard that causes the fan working inproperly.

So, I guess it's not difficult to put these pieces together, inside my comp? Also, I guess I'll have to re-install Windows, right? And Windows installing is all ready to go after you've installed these parts? This all, because I wouldn't want to wait many days and PAY for it, when they do these things in the store. I'll buy this stuff today or tomorrow.

Anything else I should think of?