I just installed a EVGA 260 GTX on my Windows 7 x64 box (ASUS P5D). Now the computer won't shutdown properly. When I shutdown, the monitor turns off, but none of the fans stop and the machine sounds like it is still running. The power button does nothing, including turn it back on. I have to cycle the power supply (either yank the cord or use the rocker switch) to get it to turn off fully and turn back on.