Is my video card fried?

[Kremerica]

hey all,
I have a older pc, P4 3.4ghz with a ASUS P5GD2 Deluxe motherboard.
windows xp pro 550 watt antec psu

I have been having problems related to powering on the computer, and when the thing turns off after a "shut down" it magically turns back on by itself, even though I dont have any of the bios settings for wake on ... turned on.

then one day the computer started to do the following:
when I press the power button, the fans start to spin, hard drives start to power up, and the power lights on the front of the tower come on, but only for 1 second. literally, 1 second on then off again, and I couldn't get the computer to boot.

So I pulled the video card and memory out, and I got some bios error code beeps, put the memory back in, and the computer loaded fine, (no video) this motherboard doesn't have onboard video either.
then when I put the x700 pro back in, it would get power and immediately shut off again.
so I went and bought a cheap ~$100 video card and put it in there and the system works fine.

when I put the ati x700 pro back in there it does the same thing again...

how do I diagnose/fix my ATI X700 pro?

thanks,

 

[MegaVovaN]

What is this cheap ~$100 video card?

I think PSU gives out less power with age, and it looks like not enough power for your video card? Though I don't recall x700 pro being a power hog.

 

[Kremerica]

The video card is a GeForce 8400 GS - PCI-E 512mb DDR2
I bought it from best buy.