I'd bet dollars to doughnuts you don't have enough power to run that.
Both Athlons and the geforce suck up a LOT of power. If you have a full tower with a bunch of stuff in it and a bunch of fans, you may be running low on power. I'd either try a high-quality 300W PS, or find a 400 or something bigger.
I'm assuming your Athlon is not overclocked.
------------------
Lephturn - Chief Trainer
A member of The Flying Pigs
http://www.flyingpigs.com "My P-47 is a pretty good ship, she took a round coming 'cross the Channel last trip.
Just thinking 'bout my baby and lettin' her rip, always got me through so far."
- Steve Earl