Don't suppose you're willing to make an attempt at fixing it/Have a heatgun handy?
My video card did the exact same thing 2 years ago, still works after I did a reflow.
If theirs no visible physical problems apparent on the vid card (Bad/raised capacitors in particular) the video card's BGA GPU/RAM chips may have broken solder joints... you could remove the heatsink, cover the top of the card with tinfoil (3 sheets), cut out holes for the ram (If it's the square BGA chips) and gpu chips, then spend 20-30 minutes (First 10 on low setting, next 10 on high, last 10 on low) waving a heat gun 1-foot to 1/4 foot at it, gradually moving closer as you heat the chips up/further away after the 20 minute mark (So the chip/solder experiences a gradual increase then decline in temperature)...
Make sure to heat the board up in a heat-proof working area though. Also, you could google "BGA/Heatgun reflow" for some more info/videos giving a decent idea as to how to go about it.