I've just water cooled my 980 SLi system and at first I thought the second card was dead because every full screen game in SLI just flickered green. It also did this occasionally on air but not as badly.
After an hour or two the green flickering stopped and SLI worked normally at full screen.
 
I still think there might be something wrong with the second card though because if I try booting with the DP cable in that card there's no signal to the monitor.
Also the coil whine from that second card has become a lot worse when gaming. Or maybe I can just hear it more now that the fans aren't there...?
 
I've started the RMA process for the second card but just wondering if there are any suggestions here as to why there's no signal plugging the DP cable into that second card.
 
Thanks.

Disable sli, shutdown pc, change display cable to second card dp, monitor won't display anything until logged into windows (this is just the way things work when running sli).
 
Green flickering could be caused by defective sli fingers. Move the bridge to the other set of sli fingers and retest. 

As far as I know, EVGA will approve an RMA request because of coil whine. Just go to your Products Page and select the board that is causing you problems and then request an RMA replacement.