Many things could cause this. I would first look at heat as a potential source.
Power supply also could cause it.
Corrupt installation of software would be a prime candidate (multiple installs of video card drivers without removing previous version first is a good one). Some software installed which has replaced a system file or DLL.
Possibly some corruption within the Aces High installation. Remove the 'cache' folder first. Next, rename the 'settings' folder and start from scratch.
Email me the DXDIAG output too.
Remote troubleshooting of something like this is very difficult to do. The simple installation of another application can cause it, or the order in which software is installed can cause it. The variables are endless.