OK. I can't figure this out. It just started today. When I try to run the Heaven benchmark in DX11 it hard locks about 15 seconds in, every time I try, without fail. It will run perfect in DX9 and DX10 with no problems. I can also pass Vantage without fail. These are the things I've tried without success: Uninstalled and reinstalled Unigine Heaven several times Tried Catalyst 10.1, 10.2, 10.3. (Used driver sweeper each install) Ran at stock and overclocked, with stock voltage, and with an extra bump (In 10.1). Afterburner voltage adjustment does not work in 10.2 and 10.3. I am running running crossfire So, any ideas? Anyone experience the same thing? Any help is greatly appreciated, as this is very frustrating.