How to properly measure CPU temperatures?

Hi, I've heard that 3rd party utilities misinterpret the TCTL signal (don't really understand what that is) and give a bad reading of the CPU temps for AMD processors. However, I tried to use AMD overdrive, which did help a little since it gave me the thermal margins, but I would really love it if there was a way to get the actual CPU temps, not just the margin. Thanks again. Reply if you have any questions.

 

Specs:

OS: 64-bit Windows 10 Pro

CPU: Athlon X4 880K

GPU: Radeon R9 285

8 GB of RAM