I recently purchased 2 EVGA GTX 980 SC cards for my surround set up. For the first couple of weeks everything was fine. The temps on both cards were good (mid to low 30s) with the top card running just a little hotter then the bottom one, maybe 3-4 degrees. Normal. Suddenly, last night I noticed that the bottom card now runs 7 degrees hotter then the top card at idle, 31 to 38 respectively. Under load in 3DMark Fire Strike the difference increases to 16-17 degrees. Previously running Fire Strike would yield 'normal' temp differences.
The change happened at some point yesterday when I was fiddling around with the Dragon Age Inquisition settings, and some very minor overclocks in PrecisionX 16.
I've tried uninstalling and reinstalling current drivers (344.75), reinstalling PrecisionX 16 and physically swapping the cards in their respective slots. One thing I did noticed is that the hotter cards voltage is at 1012 while the cooler cards voltage is at 993. I don't remember if they had the same voltage before or not or even if the should be the same. The GPU clocks are the same on both cards.
Im not sure if its worth noting but I have one dvi connection to the top card and one dvi and one hdmi connection to the second. Any ideas what the heck is going on here?