When I play Morrowind or Mafia, the monitor turns itself off after a while. The monitor power light is on, and there is sound and action. It seems to be random when it turns itself off. Sometimes I can play for hours, sometimes it's a matter of a few minutes.

I have a Radeon 9250 with the latest drivers, directx 9 and xp pro. The frequency set on the desktop/monitor properties is 60 Hz and so is the frequency set in the card's software. It appears to be the default frequency.

check up compatible fequencies in your monitor manual but sometimes the problem levels itself out (had the same problem with thps3 in 800x600 at one point) but otherwise try setting frequencies to what your monitor supports in gfx card drivers

Thanks, but I did. The monitor supports a number of frequencies up to 120 inclusive. I tried both 60 and 70, but the same thing happens.

I run in 1024x768, with as much punch as possible (pixel shading, the lot), 32 bits colour.

don't know then. like i said, it may just level itself out at some point

maybe it's time to get a new monitor...

does same thing happen with other graphic intense games? If so then maybe something is worng with graphics card or motherboard.

Try setting your monitor to other frequencies 85hz should be optimal, it might help, I don't know why but it might. :P