I have a 5770 reporting that it's running at 105C at 85 Mh/s.  Now, I know this is complete nonsense because I have, on the same board, a 5870 running at 412 at 55C.  Also, the room temp is close to freezing, roughly 40C right now, it's an uninsulated pond pump shack in my backyard and I live in the NW.

I assume this inaccurate reading is throttling the hash rate, I can get at least 215 out of that card (as I have in the past).

Any ideas on how to trouble shoot what exactly is wrong and fix it?