Just had this same issue tonight when mounting my E6600 on a P5B. Let me just say... What a horrible mounting system. I shudder to think what damage an average user might do to thier chip with such a finikey mounting system.
Not to mention i feel the damn thing needs a backplate to maybe reduce bending of the damn mobo from the HS -- That just always makes me nervious.
Anyway -- Im glad i found this thread. It was my first time with LGA-775. My temps (E6600, AS5, and stock cooler on a P5B) were also 85+ and are now down arround 30-31 in bios. But it might have still been heating up. To be honest i didnt feel like staring at the hardware monitor for more than 2 min.