What hardrive do you have?
Does your computer pass Prime95 testing?
Are you sure it's not your internet connection?
Thx to you, I found out the prob. Although I was playing single player, IT WAS MY INTERNET!!!!! Since im using wifi (too lazy to run an ethernet cable but have to now), its constantly sending a signal back and forth. I've played games with wifi on before, but whatever. I unplugged the adapter and works like butter!!!