Yeah I am using the latest drivers, and my case ventilation is decent but it probably could be better. I've got a fan on the back for intake, near the cpu, and one on the side for outtake. (I wonder if reversing the airflow would help?). I recently cleaned out all the dust I could find from the computer, including the graphics card, but I didn't actually take it apart to get inside it. Maybe I'll try that and go with that arctic cooler if I need it.
Do I need to worry about whether or not a replacement HSF will fit my card (which is a BFG), or will any work as long as it's built for a 6800gt?