It definitely could, although in an ideal world when a manufacturer overclocks, it would always be stable. You could try to clock it back down.

It is really funny that GTA3 still runs fine, since those games are on the same engine. Check the settings you're using for that game. Maybe it's running on OpenGL or something....

Also, try to get the game to crash with the sound disabled in the game or the card disabled in device manager. Then you can rule out that as a possible problem.