Xfx black edition 6870 1gb strange problem

[Zestypanda]

Ok, so I will try to include as much information as possible.
I installed 10.8.2 fine, for audio, Ethernet, shutdown,sleep,restart working. But every so often the system will halt, display a black or grey solid colour screen with white vertical lines going down it. Something is causing the display server to crash. Anyone experiencing this?
System is a core i5 2300 3.67ghz. 1680mhz gskill 4x4GB ddr3 ram, AMD XFX 6870 black edition 1024mb, 500gb WD blue, asus p8p67 pro m with custom flashed bios, all settings in bios are set according to hackintosh guide, achi mode, virtualisation, turbo, etc. What is strange is that it randomly happens. It's not like it happens after a specific amount of time, it could be anywhere from twenty minutes of uptime to jut a mere five minutes. Though I do notice that when I'm running graphics intensive programs it is more likely to crash. When I was trying to download an update from the AppStore it locked up and crashed yet the Ethernet was still active so I know it's the display server that's gone kaput, when I was trying to watch a DVD in QuickTime I got ten minutes into it an then it crashed.

 

[Zestypanda]

Ok. It defiantly is graphics related. I was able to let the system idle for a good fourth minutes and it didn't crash, I then went and switched between workspaces and widgets and open applications and on the third switch it crashed. It crashes to a white background with black and white verticals stripes, sometimes black background with white vertical stripes, I have also seen it crash to a solid grey, blue, and red background.