Weyland,
If you have an Intel chip, you can read the chip's temp by reading the internal thermal diode...if your mobo/bios/chipset supports reading the diode.
If you have an AMD chip, then the various temp sensors/thermistors will tell you the temp of their internal sensing elements wherever they happen to be located...which will be some temp between the internal chip temp and case ambient...but it most certainly won't be the chip's internal temp.
The best you can do with these "psuedo" chip temps is to "compare" them to other hopefully similarly located sensors. Example, John Doe has a similar chip/mobo/system and is stable at nn degC, hopefully you can compare your reading to his. Or, you are stable with a cpu intensive app at nn DegC, then later your reading at this app increases significantly...start to worry.
John C.