Gateway FX crashes while playing games or watching video on AC power.

[christhehut]

I have a Gateway FX laptop with an Nvidia 9800 graphics card. Whenever I try to play any kind of games or watch a video, even from YouTube, on AC power, my display goes black and the sound loops. This doesn't happen on battery power though. The only way to get out is a hard reboot. When I was running Windows, I could solve this by forcing a constant preformance level with RivaTuner. Is there anyway I can do this in Ubuntu 11.10?

[christhehut]

I've fixed it. I enabled the overclocking tab in nVidia X Server Settings and lowered the speeds. I've been playing Morrowind for a few hours now with no crash.