Yea, I think my videocard is failing...

I moved recently, and since then, I've been unable to play any games full-screen. If I go full-screen, the monitor turns off and on after a few seconds, getting faster and faster until I either exit the game or reboot. I figured it might be heat, so I have a window fan running directly into my case right now, which helps a little bit but doesn't fix it. I also thought it might be the monitor, so I tried another one to no avail. I can play WoW in windowed mode fine, but Deus Ex full-screen, Live For Speed full-screen, Counter-Strike and Half-Life 2 all see this problem. Could this be anything other than the videocard? I don't want to have to shell out money for a new one.

It could be your drivers. You can also try reinstalling DirectX.