Use Isopropyl Alcohol to clean the top of the cpu. You can find it at Wal-mart in the medical department where you would find band-aids, neosporin, and the like. Try to get the 90%+ one instead of the 70+ one. You'll also need the lint free cloth. The ones used to clean glasses lenses work well. You can probably get one from 20/20 eyeworld or something hehe. I never did look for one at Wal-mart but you may find one their if you ask one of the roaming salespeople.