How hard is it to replace a processor?

[BOSSNIG]

It's as easy as taking the heatsink off, moving a lever, pulling it out, and reversing that. That's it for the physical part.

You need to find one that matches your slot, and wether it will even work with your board.

How do I figure that out? :B

Start by finding out what board you have.

you should be able to go to start>run>dxdiag to tell what board you've got. from there, go to the manufacturer's site and look up what FSBs and socket it supports.

I'm using Vista.

I think it tells you in the computer section in Vista, not sure though.