Hi,
Would be helpful to know what all you have already tried to avoid giving the same suggestions. Till then try the following.
1) (Obvious) Uninstall and re install drivers.
2) Once thats done make sure you go to the AMD Catalyst Panel and set setting to AMD and not individual programs. (In all settings)
3) Check and try changing the resolution (Should be native)
Also, would be helpful to give your hardware specs in such cases.