Internetwhizzkid i also seem to have this problem regarding one of the temps,ive used speedfan on several computers to diagnose possible problems.
Im starting to wonder if its as reliable as it used to be ! as the system thats gives me a high temperture runs perfectly for long periods of time (12 hours continuously)or more.
I have chaged the heatsink,and the psu and i still get this one reading that is high.
If your system is running ok,and no alarm or warnings that you are overheating..i would guess that speedfan is not reading the mobo information correctly as with mine.
This is from my experience using speedfan.