seems like your 2nd and 3rd gpu arnt getting used much. 1 and 2 degrees difference from idle and load? you running at 2560x1600? to take full benefit of 3x sli? anything less would be a waste imo.
It could be that the 1st card is malfunctioning. Over 80c is very hot. My 9800GX2 would crash when the reported temps got to 81-87C. I would put the 1st card in the 3rd slot and see if the temps even out, then.