Air flow makes a HUGE difference. When I was running the AMD OEM cooler, I could still run 200 x 12.5 if I took the side of the case off and put a 10" floor fan pointing in the case. With that setup, I could hold 48 C running prime95. When I go to this one LAN party where the A/C sucks, I have to crank my FSB back down to 180 @ 1.65v or my temps get out of control. The ambient temp at the place gets up to 82 degrees sometimes!
Right now I have two 80mm front inlet fans, two rear 80mm exhaust fans, and two side mounted exhaust fans near the CPU/vidcard. I may reverse the side mount fans again (in inlet fans) as it seems to help my temps to blow fresh air in right there by the CPU/vidcard. I have a couple of open drive bays that I'm going to add fans to as well. Running the AMD OEM heatsink with that fan blowing on it really sold me on case ventilation.