A lot. But no one will be able to tell you how much exactly, because it varies with a lot of factors, like CPU, ram, game and its settings, resolution, list goes on...
Haha but im only 12 and im not sure my parents would know what to do but i could try i guess, I dont have any equipment for it, would i need to to take the motherboard out of the case and do i use anti static bands and stuff? lol
All the equipment you need is a philips (+) screwdriver and a pair of dry hands. Anti-static bands is just to eliminate static, which can be done by simply touching a large metal object (it has to be conductive). Search youtube for some videos about it. Do it yourself and save some money.