graphics card dying?

[novie]

could use some support/insight on this one from all of the kind people of PCMech...
been running a new build in fine and stable fashion for 3+ weeks. the last couple of days the monitors are losing signal from the computer (they run fine from other source). on restart there may is generally nothing but the signal search thing, or there may be a signal for anywhere from a couple seconds, to a few minutes, during which the system appears to be running ok. used those couple of minutes to uninstall/reinstall the graphics card drivers, then just when i thought it was good, the signal dropped. maybe it was from hitting ctrl-alt-del a bunch of times, but on on restart it said something about overclocking attempt failed, so i did the cmos jumper thing to reset the bios... came back for a few minutes and i thought i had it, but then click, the monitor signal went out again.
is this just the graphics card dying out? i didnt make any changes to the system immediately prior, used one of those verbatim thumb drives the day before this started, but i wouldnt think drivers from that could cause this and i have no reason to suspect spyware/malware. wish i had a spare graphics card to throw in there and test. help!

asus p5b deluxe
nvidia 7900gs
core 2 duo
antec p180 case
windows xp
2gb corsair
2 samsung 226bw

[Cricket]

What power supply are you using?

The problem could be the video card but it could also be another component (like the motherboard) is causing this. Without testing the video card in another computer you'll just be guessing if it is the video card or not.

Cricket

[novie]

thanks for the reply
psu is ocz gamestream 700w. have no outright reason at this point to suspect it, obviously im no expert- but the rest of the system seems to be powered ok fwiw. though now that i have the case open sitting next to me, i detect a subtle change in the sound from the graphics card fan when the signal flicks out. dont know if thats a symptom of uneven power. since i dont have a compatible case lying around testing these components in another rig is unfortunately not an option. running an older pIII win2k machine and a laptop in its place and cant swap with them. curious, why would you suspect the motherboard?

[Cricket]

Originally Posted by novie psu is ocz gamestream 700w. have no outright reason at this point to suspect it, obviously im no expert- but the rest of the system seems to be powered ok fwiw.

When troubleshooting computer problems it's best not to assume anything.

Originally Posted by novie though now that i have the case open sitting next to me, i detect a subtle change in the sound from the graphics card fan when the signal flicks out. dont know if thats a symptom of uneven power.

It's possible the video card power circuit has a problem with it.

Originally Posted by novie curious, why would you suspect the motherboard?

Because the video card is installed in the motherboard and that's where it's getting it's power from. If the PCI-Express slot has a problem with it it'll show up through the video card. I've seen cases where the monitor would lose image from the video card but when the video card is put into another computer it works fine. Put a different video card in the first motherboard and the same problems show up...result: a bad motherboard.

Cricket