That GPU arrived in 2012 so it's old enough to have age issues. Sometimes I find the million mile work (heatsink compound replacement and cleaning of the machine, fan check) to be enough. There have been owners that don't want to have the work done because they want a guarantee. For that we start replacing parts.
I have three monitors, all going through my video card (EVGA 670 FTW). Two or three times now in the past couple weeks, as I'm just going about my daily business (as in, not stressing my card by gaming), all monitors will go black except for the mouse cursor: That can still move and even travel across monitor screens. Then, after a few more seconds, sound cuts out and the mouse disappears and the monitors are completely black, although the computer is still physically on.
My question is, is this more likely to be a problem with the motherboard or the video card, or something else entirely? And how do I tell?