I literally only just swapped back to NVIDIA because I had had enough of AMDs drivers causing me issues, can't complain about their hardware, they just need to sort there drivers out.
well, good for you but this is not everyones solution.
I also have some weird problems since after 12.4 drivers.
Video: http://www.youtube.com/watch?v=CalsaO3auuc
The past days ago, I tried to get it to work with 12.8, but whatever I tried, it didn't work. I have two cards in crossfire and was thinking that maybe one card was broken - no it is not.
I have noticed that the problem is caused by the use of DVI + Mini-DisplayPort. Maybe it doesn't happen with other combinations.
When I select the MiniDisplayPort monitor to be the primary monitor, two monitors begin to flicker/tear.
They only tear in FULLSCREEN 3D applications. I can run windowed 3D apps just fine.
Also the monitor(s) do not tear in every game. Sleeping Dogs runs just fine while CS:GO/NaturalSelection2 etc doesn't.
ONLY SOLUTION FOR THIS ONE (Tearing) (V-Sync does no difference):
Uninstall the driver (go to software and uninstall it), reboot, install CAT 12.4 or EARLIER. . (note that uninstalling the driver, i.e. 12.8 might take up to 20 minutes because it COULD be bugged as hell... it's been like that even on the 2nd try. Just let it do it's job and wait...)