AMD CPU wrong temperature reading (thread no. 1.259)

[o0o]

Hi,

I'm new to TrueNAS and my system is running stable. I used the search but couldn't find an answer to this:

TrueNAS doesn't show the correct temperature of the CPU. It's an ancient AMD 64 3000+. The BIOS and the formerly used Windows were reading plausible temperatures.
TrueNAS shows a range between -13°C to +8°C. Probably realistic seems to be ~30-40°C higher.
Unfortunately, I couldn't find any settings in TrueNAS to change "something".

I was reading many threads in the forum regarding this or similar problems, but couldn't find any solution. (I'm no coder, so I maybe didn't undertand what I was reading.)

The system was running for years and often for weeks online. Often with full CPU load. So, I know, the system will not overheat. But anyway it would be nice to see the correct temperatures.

I wonder, if anyone could kindly help me with this. Thanks :)

 

[Samuel Tai]

According to the source code for the amdtemp kernel module, there should be a sysctl to set a temperature offset. What does sysctl dev.amdtemp.0.sensor_offset indicate? You may need to adjust this via System->Tunables to set a offset correction.

 

[o0o]

The result is: 0
So, no offset set. The range from -13 to +8 seems to be realistic. Any idea, how to calculate the real offset?

What exactly shall I enter in "tunables"?
Variable:
Value:
Typ:

Thank you!

 

[Samuel Tai]

You'll have to experiment then with offset values to see if they'll correct the graph. For the tunable, enter:

• Variable: dev.amdtemp.0.sensor_offset
• Value: Some integer. You'll have to experiment with positive and negative values
• Type: sysctl

The tunable takes effect immediately, but the graph may take a couple of minutes to reflect the change.

 

[o0o]

Thanks a lot, it worked. I will experiment with some values.
Great forum!