I suspect a heat related issue. Can you run the PC with the case open and a fan blowing cool air on the video card? If it works OK with the fan - then you have found the problem. All you did was plug a LAN cable into the back of the computer or did you put some kind of internal card to connect to Qwest?
I restored the computer to before I downloaded all the Qwest junk and Norton. Granted, I had to re-install WOW, but the problem is gone. Instead of installing Norton, I downloaded Comodo internet security for free. Everything runs as it should, prefect. So that tells me it was either one of the Qwest programs or Norton.