Thanks Equill. It was the CUDA that I pressed, while powered down, but apparently did not hold the switch long enough. Will go try again. The problem(s) the 9500 started displaying after video board swaps are (1) most of the time the CD drive is not recognized on the bus, or if recognized it won't mount a disk, and (2) ASP hangs the system when asked to scan the devices. This all on a machine that was working fine prior to the video card swaps, even though I have returned the configuration to the original.