Yep, this is an old post but...

the100thmonkey is nearly there...

It's not Speedfan's fault exactly, it's the BIOS's. Temperature sensors don't actually report a temperature...not like we think of it. They report a integer value, usually between 0 and 255. This has to be offset to find 0-point. If the offset is wrong, it'll report 95C instead of 45C or whatever.

Speedfan makes the mistake where the manufacturers own monitor software or software with a built in shim compensates. I seem to recall the offset is actually configurable in Speedfan.