Video card stopped working

[CD82]

So there's this friend of mine who until recently had two nvidia 8800 gts (g80 version) in sli mode. Now one of his cards (the primary one) stopped working in his pc but still works in other pcs. The things he tried:

- swapped both cards (making the no-longer-working card his secondary)
-> no change, still only one card recognized
(from now on all tests are with only one card)

- only used the no-longer-working card, in both the first and second pci-e x16 bus
-> no image displayed on the screen

- tested both pci-e buses with his other card, which worked in both buses
-> both his first and second pci-e bus are working properly

- tried both power supply cables from his psu on the no-longer-working-card
-> no image

- tried both power supply cables with his other card
-> image in both cases

- tried his no-longer-working card in another pc
-> card works fine, image is displayed

- back to his gamer-pc
-> card no longer works, no image on screen

so all his pci-e buses and both his cards work fine, one of them simply stopped working in his gamer-pc. We are both quite baffled by this. Any ideas? (now he wants to trade his g80 against my g92 which is kind of a bad deal for me... so I'm not gonna take it)

 

[ESPNSTI]

A bit of a long shot, but try this:
Have the bad card in the primary slot, remove all other cards.
Then reset the BIOS to factory defaults using the reset jumper on the motherboard or otherwise.

Was he using a dual monitor or tv-out configuration?
If so try plugging in the secondary monitor in the primary output and the primary monitor in the secondary output.

 

[CD82]

Just one screen.
I'll give the bios reset a go, see if that changes anything. Thanks for the hint!

damn computers anyway. I love them to death but sometimes things go wrong for no reason whatsoever and if you built the damn thing yourself you are just left alone, wondering "wtf why did that just happen?"

 

[Buba]

So the card stopped working before or after windows is loading?
It doesn't even show the Bios and stuff? That is weird... Any chance he can get a the same Mobo again for cheap?

 

[CD82]

No image at all. Putting both cards in and attaching the screen to the still-working card brings up windows, which shows only one card installed. It's really weird. And apparently the board works fine because his other card works in both slots. Don't know if the board is still available, but might be worth a try.

 

[CD82]

Just a little update:

gaming computer + 8800 gts 640 mb = no image at all, booting with a second graphics card shows that the 8800 is recognized as a "pci to pci bridge" in windows, and sisoft shows three nvidia devices in the pci-e slot where the card is placed, but they are just listed as nvidia + random numbers. Bios reset didn't do anything, but we tried the card in question in a third computer which also doesn't recognize it (it still works in a second computer though).

 

[ESPNSTI]

Very weird.

I don't think this will help, but I'll mention it anyway.
Maybe the firmware on the card somehow got messed up.
If that is the case, if you have the exact model, version, etc... you could download firmware from the internet and re-apply it.

 

[leviathan]

Just a thought... is there enough power in the rig to run both cards? How powerful is the PSU and what else is installed in the case - custom coolers, hard drives, more extension cards?