MSI high temp on NB

I have MSI 865P-Neo2 board and I get the weirdest temps in Sandra.
It is showing cautions on the following:

Power / Aux Temp 54.5C
Chassis fan speed 2482
cpu fan speed 5273
cpu volts 1.46v

The system has had weird lockup issues. I am assuming from heat.
I don't have this machine overclocked.
Why is that power / Aux temp so high?
The MSI core center registers that temp as the north bridge.
Please help.

Does the northbridge feel that hot when its running?

The heatsink/fan doesn't feel that hot, but it wouldn't be as hot as the actual cpu.
It is weird.

from what i have heard, some of the msi boards with the LED light show on the NB fan have the heatsink not seated properly. You might want to play with that.