Ever since I upgraded to windows 7 I can seem to play any games with my PC rebooting either straight away or after a few minutes of gaming, after reboot I get bios beeps for gfx card failure. The same PC worked fine with windows XP and vista.
The card is a Sapphire RADEON HD 4850 512MB. The games seem to run for longer if I turned down the graphic details and I set the fan to run at 100%. The card idles at 45 degrees C.
Iv updated directX to 11 and got the ati drivers to 10.7, and have even fitted an aftermarket heat sink to the graphics card, but it doesn't help.