1. Uninstall ATI and Intel Graphics Drivers (if you can't find it in Add/Remove right click My Computer>Properties>Hardware tab>Device Manager, find the entries and right click them to uninstall)
2. Go into your bios and disable your Onboard video, see your motherboard or computer(if its from Dell or something.) to see how to do this, DEL is usually the key to get in.
3. Get
DriverCleaner and boot into safe mode (F8 before the windows boot logo shows up) and clean out the drivers
4. Install Ati drivers from ati.com