cparnell- your video-card compatibility clue is a good one. Eric84- I've also had to trace my ram for a bad chip, and another system just needed enough ram. This last is also a real issue when the video card shares RAM with the main processor, and when video is embedded on the motherboard (also sharing Video RAM with the main processor). These are all things to check out. Fortunately RAM & video card issues are relatively easy to fix, and usually fairly inexpensive, too.
Good Luck,
cfee