This PC runs everything perfectly fine. The computer's core and gfx never go above 40C and 50C respectively. There is a hitch, though. Whenever I try to run any game (for example, Shogun 2 or Dragon Age 2), in DX 11 mode, the screen turns off, and I am incapable of doing anything beyond shutting the computer off via the button on my logitech keyboard. These same games, run in DX 9, work fine. Obviously, I purchased the HD 5850 expecting for DX 11 not to be a problem, so this irks me quite a bit.