CPU Temperature: Trust the BIOS or 3rd party software?

[ArcaneLeviathan]

Here's a story for you. Two years ago I built my PC. Everything worked fine (and is continuing to work fine). Back then my BIOS temps were around 30-40C. That's didn't alarm me. I never bothered checking third party software for my temps. Recently, now two years in the future from my build, I decided on a whim to check the temps because my ambient temperature changed and my PC was now under a desk instead of on top of a wardrobe (you read it right). The results? Not good. Every 3rd part software I tried like Speccy, CPUID HwMonintor, SpeedFan... you name it and I've probably tried it. They all give different temps than the BIOS. Trusting the software over the BIOS I put as many fans in my case that I could, liquid cooled my CPU, and applied aftermarket thermal paste...several times to make sure I was doing it correctly (yes I properly removed it each time). After all of that, and to my great joy, the BIOS temps were at ~25C. I figured the third party software would show desirable temps but I idle windows at 60C like before. So now I have a much louder and more expensive system that cools just the same.

I read that some people are having the reverse problem where the BIOS shows higher temps than the software but I have yet to find a solution to my problem. Any ideas?

 

[smorizio]

with the bios temps check when you turn it on and after it been running for a bot to see if the pc is air starved. 3 party cpu temp have 3 line nows. show min/max and current temp/ make sure your reading the current temp line.

 

[geofelt]

What is your cpu, gpu , cooler and case?
At idle, a well mounted cooler should show about 10-15c. over ambient.

I might be concerned if your case does not get sufficient intake air.
Take the case covers off and see how much that helps.

I would trust the Bios temperatures readings for idle temperatures.
Under load HW monitor should be accurate, I can't say why it seems to differ so much.