Problem with X1900GT

Hi guys, I have a problem with my X1900GT

Here's my system setup -

Powercolor X1900GT on Catalyst 7.1 Drivers
Topower 500W PSU
AM2 3500+ CPU
MSI K9NGM-L Mobo
1 Gb 667MHz Patriot RAM
Win XP OS

I haven't overclocked the card; it is running at stock speeds.

When I play Dark Messiah of Might and Magic(patched to latest version), the screen sometimes freezes in the midst of playing and blacks out for about 3-4 minutes. I can hear the fan on the card get instantly louder while this happens. After a few seconds it quietens down, and 3-4 minutes later the game resumes at where it was before the screen froze.

This happens every 10-15 minutes of playing so it is quite irritating. I tried lowering the settings(HDR, AA, AF, no shadows, etc) but the problem persists. What might be the problem?

I haven't overclocked the card at all, I imagine the stock cooler is adept enough to handle it. X1900GT was supposed to be betn 70-80C when running 3D apps anyway.

I calculated with various online power calculators before buying my current PSU, and it never got close to 500W. I don't overclock my CPU or RAM, and everything runs at stock voltage. The efficiency of my PSU is at least 70%. And yes, the 12V rail supplies more than enough, according to Powercolor specifications.

Anybody experienced a similar problem before?

Brought the card to vendor for testing, he says there's something wrong with the RAM. Still under warranty so I RMA-ed.

Thanks for the help anyway.

Those temps are fine, my runs at similar temps during games too.

I got that few times too, until I got rid of the Catalyst. Since you RMA'd, then hopefully your new card won't be causing issues.