Antec is good to stay with. If you get a PS with a 24 pin plug, make sure the extra 4 pins are removable, most are, if you still need the 20-pin. A good, high powered power supply is a good thing to have, as an upgrade, whether you "need" it or not. The power supply isn't some piece you replace ONLY when it goes bad. It needs upgradeing just like any other part. However, I still can't say if that is your issue. I'm just saying, if you have the money, it's not a bad buy either. And where do you see "PFC"? I don't see what you mean.