I have an eVGA 6800U that came clocked at 400/1100. The best I could get out of it is 435/1150. The drivers will let me do 440/1160, but then I get artifacts. Any higher and the drivers reject it. My system consists of an AMD64 3200+, 2 GB of ram, 2 optical drives, 2 hard drives, a sound blaster audigy 2zs, and the 6800U. This is all driven by a 320W power supply. I'm wondering if I could squeeze more overclocking out of the 6800U with a bigger PSU or do I just have one of the crappier cards?