not sure how to troubleshoot nvidia 7900gt graphic prob

[Christian Darrall]

the only way i can describe it is a non clear image an certainly a non usable image,

this happens every so often i reboot my pc and it happens throughout the bios loading screens and everything, i leave my PC off for about 5-10 minutes then its fine, until i launch a game then it starts over. hasn't happened recently (past week or so)

can any one tell me what the problem is

 

[The_Other_One]

Overheating, perhaps? Could you get a screenshot?

 

[Christian Darrall]

i did try screenshooting it but it came out normal (when it was working right)