For those who are always on constant watch of their rig temps, HWMonitor provides a decent temp monitoring tool. One of the questions people always ask is around TMPIN0, TMPIN1, and TMPIN2.
There are a lot of different opinions as to what those three variables represent. One of HardwareCanucks.com OP members posted this finding:
Comparing HWMonitor with Everest Ultimate I get this...
BIOS - HWMonitor - Everest
SYS = TMPIN0 = Motherboard
CPU = TMPIN1 = CPU
MCH = TMPIN2 = Northbridge
A slightly different finding was posted by an OP at Overclock.net: