Questions about CPU heatsink and reported temps BIOS vs OS
I just installed a new heatsink fan combo because the stock one was having issues where the fan would not run sometimes.
I installed a new heatsink, one of the tower type ones with the fan on the side and direct contact copper pipes going to a large aluminum heatsink. When I installed it I looked at the temperature on the BIOS and it was hovering between 48C-50C. I installed two programs Core Temp and Real Temp and both of them are reporting 32-35C at idle. That's a pretty big difference and I was wondering if the BIOS could be reporting the temps wrong.
Questions about CPU heatsink and reported temps BIOS vs OS
It is normal that the bios and and software program report two different temps but not as much as you are seeing. Have you tried seeing if your motherboard manufacturer makes a software to measure temp.
You could also put a load on the processor to see if it rises quickly so you can determine if the software is measuring the correct sensor.