Cpu temps what going on?

[Dave0w]

ok am using Core Temp, Hardware Monitor, and Real Temp.
They are all telling me that my CPU is running at 18/20c idle, but BIOS is saying 36/38c idle what do i trust.

CPU: AMD Phenom 1090t @ 3.6Ghz turbo core disabled. stock voltage
MoBo: MSI Fuzion Power

 

[smithy83]

degree celsius and degree Fahrenheit maybe?

 

[Krono5]

Bios and those programs read different sensors iirc.

 

[Dave0w]

Bios and those programs read different sensors iirc.

so is the CPU temp 18 or 38

 

[Krono5]

Oh and you shouldn't use all of those programs at the same time as they can mess with each other and give incorrect readings.

 

[Krono5]

so is the CPU temp 18 or 38

18, pay no attention to the Bios temp.

 

[OhEsEcks]

TCase = thermal reading from CPU heat spreader.
TJunction = thermal reading from individual CPU cores.
TCase Max = thermal limit recommendation that TCase should reach.
TJunction Max = thermal limit cores can reach before throttling occurs to prevent damage.
DTS = Digital thermal sensor.

Most BIOS software reads TCase where a thermocouple is embedded in the heat spreader that covers the individual cores of the CPU.

Most desktop software reads TJunction which is associated with the actual CPU cores. The CPU cores have a DTS in them.

In Intel and AMD chips they use specific formulas to output TJunction. For intel it is TJunction = (TJunction Max - DTS output). I can't remember the AMD formula. VIA output the absolute temperature so there is no formula needed. What it says it what it should be running at. However it is said that DTSs are more inaccurate at lower temps and only get more accurate the closer to TJMax they get.


All in all monitoring temps and dealing with temps is something that gets very boring very quickly when you're looking into it. I've built PCs for years and there is not one single piece of software that I believe is telling me the accurate temperature of the cpu cores. Not one. I simply stopped bothering monitoring temperatures. When I build a new machine, I will stress test it to make sure everything is working right and I will monitor the temperatures then to make sure they're within limit. But after that I simply forget about it. TJunction Max exists, so if anything does go wrong computers should shut themselves off before any permanent damage occurs.