I think it's driver issue, so you should post this problem to a driver forum. Besides, I think it maybe relates to display model. You need to set as hdmi display only.
I am sure its not a driver issue - my brother has removed it and re-installed it ..
Try the following resources:
- Try posting Radeon questions here: http://forums.amd.com/game/categories.cfm?catid=433&entercat=y
- Contact AMD support either by email (http://emailcustomercare.amd.com/) or by phone (http://support.amd.com/us/contacts/Pages/global-technical-support.aspx)