The only other thing based on what you described of the card is that you have insufficient cooling in and around your case. Try to get a case fan either inside the case (some jury rigging required if you want it to blow in the cards direction or above the card as an exhaust fan. Get the hot air out of the box.
Depending on where you live its also been very hot lately, so get a fan in the room to blow around the case to move that hot air away from the case (especially if its on a desk near a wall or under a desk).
Generally, unless you have a really crappy case, taking the side cover off is not a good idea, but depending on what you have going there, you might want to consider taking the cover off and getting a fan to blow right into the chassis.
Thats my best estimate that you can try to get that guy down a bit.