Games Crashing

Hello,

Around 5 months ago I had an issue whilst playing games. It would play fine for around 10 minutes and then crashing, the only way to exit was to pull the power cord out. I updated from bios a9 to a11 which fixed this issue. However I recently started playing Hitman: Absolution and it would play fine for around an hour and then start lagging unbearably. So I updated to bios a12 hoping to fix this issue. Now again the game plays fine for around 10 minutes and the screen goes black and they says Directx or something has crashed. I then press Okay and get sent to the desktop. So a similar issue to before.

Anyone know any fixes? Cheers