Hey all, I have a question I'm pretty sure I already know the answer to, but here goes anyways...
So a month or two ago I purchased a "EVGA GeForce 9800 GTX+" 512Mb PCI-E graphics card from a private seller who had just upgraded theirs. I had previously seen it working perfectly fine on their tower 2 weeks before I bought it so I didn't mind buying it from them used. I got it home and installed it on my system. Drivers went on properly and everything else, it displays my desktop and everything fine until I try to run any games. ALL games and apps that rely on the GPU to run crash immediately, so I checked my Device Manager, to discover that my PC tells me it failed to start properly so Windows refuses to use any of the features I bought it for. When I asked the seller if it had died and been the cause of their upgrade I was given the answer that because I am running Windows 7 x64 it is not compatible with my system and if I wanted it to run properly and not have any issues I have to upgrade my system to Windows 10. Now, not having ever heard of anything like this before, I decided to do a little research to see what I could find out. So far, I have found NO EVIDENCE that this is the case, but because I like to be sure about my facts I am asking it here now. So long story short:
 
Is this specific Graphics card only compatible with Windows 10 and not Windows 7?
 
As I said I'm pretty sure i know the answer but would just like to be 100% sure before making an issue out of this with the seller. Any help would be awesome. I hope to hear back from someone about this soon.

Welcome to the forums..The card is definately compatible with your OS and drivers are available up to Win10..I ran an EVGA 9800 GTX on Win7 for a while, and Win10 too.
 
You should list your system hardware (mobo, PSU, etc.), But it sounds like the card has failed..It likely was failed when you bought it..You can check if there's any EVGA warranty on it by going to the EVGA home page, then Support, then Guest RMA..You may need to register the card first.
 
If it's possible, try the card in another PC, or take it to a PC repair shop for testing.
 
If all else fails, you can disassemble and bake the PCB (as I have done, more than a few times) and hope for the best, as solder cracking was not uncommon during the GeForce 9 Series era and caused problems like you describe..This can be discussed/explained later if neccessary.
 
Covering a lot of bases here..Post back again.

There's a PCB back side pic here (BFG should be the same) if it helps..If you can save the picture, then open with Paint (or whatever), and circle the location and post it I can look on my 9800 GTX and see if it has it, but I don't see any C684 around the GPU right off..I don't see why you couldn't snag one from another old card and use it as long as the same value as what's needed, never tried it, dunno.

That's thing can't be worth much more than $20, I wouldn't bother repairing it.