Afterburner seems to have a hard time with two gpus. I have two 7870s at different clocks and afterburner doesn't seem to know what to do with the second card. Most of the time I can't get any gpu2 stuff on the graph except usage. Other times it will report my clocks completely wrong, but CCC gets them right. Anyway, can you see temps in Nvidia control panel? If not, then gpuz would probably be your best option for temps.