Maybe this link with solutions will be able to help you - it is on askubuntu which on some other posts you've mentioned you have issues with but I still think this thread on that forum may prove useful to you since it mentions the stuff you've mentioned:
eh...yes, quite a bit actually.
I mean, it is still within the safe operating temperature range
But to be honest, It might be that either the sensor has a defect or the sensorchip is not recognized, unless you are cooling the chip with liquid nitrogen ofcourse