So to put it simply....
I bought a 9600GT and installed it. No problem so far.  
When i started a game (World of Warcraft), all went well, for about a hour....though the temperature hasn't been heigher then 47 (everest number) , suddenly my monitor goes into power saving mode, and i have to reboot. (just gusseing here, but i think the gpu shut itself down).  
If i try again, the results are the same.
 
So, i ran a stress test to the GPU. The temperature goes up to 68 ,69, no problem, no black screen, all is well.
Now i have a power supply of 460 W, 2gb DDR2 667 and a pentium D 1.8.
 
 
Some help here plz! What am i doing wrong to have this shut downs?
 
If you need any more info just ask.
 
Thanks

Hmm, reinstall drivers, uninstall all the old ones too. Reinstall WOW, Try a different game.

What brand is the PSU?  I'm suspecting the PSU might be too weak to power that card.  Or either the card or PSU may be overheating.  Get a case fan, and put it directly under the PSU to suck hot air underneath it, see if that helps, if not, I'd probably look at another PSU and maybe a PCI slot cooling fan to go under the card to pull some hot air off of it.  But do try drivers first, just in case.  

I'm reckon it's drivers or the PSU. These cards can't get hot unless you try to make them hot.

you need more memory or turn off back ground stuff
 
close all browsers, leave only anti spy virus on

I'm also thinking PSU.
 
Sheesh, a 1.8GHz PD?

 
PSU quality comes into question, I agree. What PSU are you running? (brand and model)
 
 

 
And with your system, you know all about heat  

How long did you perform stress test on your GPU? Is it 1 hour no problem? Didn't you conduct the stress test for your CPU? I really wonder your PSU maybe something wrong when temperature up or just unstable. So what is the brand and model of your PSU?

Yep, official Core2 overheater here. Why let your CPU overheat by accident when you can do it on purpose?

Pentium D? 1.8?

Sorry for the delay.  
 
My PSU is a eurotech  FPSPA460SA. I ran the cpu stress teste for a hour. no problem Running now the 1 hour graphics stress test.
 
If the problem realy lies in the PSU, is there a way to buy something like an external PSU, just to feed the boar? What i am looking for i something else (cheaper) than buying a new PSU, if the problem realy lies there.
 
Thanks Everyone

Its driver issues. I had that with the 9800 GX2 using forceware 174.74. I am running 174.93 now and it hasn't happened at all and I'm not seeing any frame rips either

What drivers do you advise me then?  
Im running the omega drivers 2.169.21 (Forceware 169.21) for win xp.
Passed the 2h graphic card stress teste by the way

try these, they are leaked nvidia drivers compiled by a third party group...
 
http://www.driverheaven.net/vista- [...] ost1140620
 
there are known to be issues but I haven't run into them. you can always uninstall them.

no sry m8 didnt work. Cant go past the windows log, got a blue screen. Uninstalled them.
 
So i still have the same problem. I removed everything so the PSU only feeds the Sata, the MB and the GPU and 3 fans. Stil crashed.
 
Ned help plz

I can't even find the manufacturers website for that PSU.

Not all PSU companies have websites.