I run an HD 6850 I get the small tear/distortion flicker when I go up and down stairs or some bumpy terrain. Forcing v-sync from CCC does not resolve this issue. I assume I would need to force a higher refresh rate because bumpy terrain = shaking camera and thus causing it because the screen isn't being refresh quickly enough. Sad thing is I have a 2ms response time monitor as well.

Also note this does not occur in windowed mode. It is something to do with full screen mode, I would run windowed mode... if it didn't cause a random crash now and then.

Last, forcing v-sync made things a bit more choppy. Your better off dealing with the tearing lol.