What the different hardware temperatures listed in psensor, sensor viewer etc reffer to?

Question

I have installed psensor and see a list of temperatures, but listed as ”Temperature 1”, 2, 3 etc . I can only guess where the processor is: but who's who for sure?

The same question stands for Sensors Viewer.

I can also type

sensors

in Terminal but I get no more than that

acpi -t

gives

Thermal 0: ok, 65.0 degrees C
Thermal 1: ok, 37.9 degrees C
Thermal 2: ok, 56.0 degrees C
Thermal 3: active, 71.0 degrees C

Considering psensor, I know for a fact that: - the temperature that varies most depending on the CPU use is Temp1 and it is one of the two highest - the other high temperature is Temp4 and it goes to the ceiling when using youtube/flash - Temp2 is very stable at a medium level of 50-60 degrees Celsius - Temp3 is by far the lowest and most imobile

So, I guess Temp1 is the CPU temperature, and Temp4 is the GPU temperature. Temp2 and 3 must be the motherboard and the hdd.

Does anybody know for sure?

Solution 1

From here:

1. Psensors makes use of lm-sensors and hddtemp to get the temperatures, so you need to install these two packages:

   sudo apt-get install lm-sensors hddtemp
   

2. To get the hddtemp daemon to run on boot, use the following command:

   sudo dpkg-reconfigure hddtemp
   

and select "Yes" when asked if hddtemp should run at boot. Select the defaults for the other questions.

3. Next, you need to set up lm-sensors by running the following command:

   sudo sensors-detect
   

And answer "yes" to everything.

To avoid a system restart, run the following command to load the modules required by the sensors:

sudo service kmod start

(if no sensors show up in Pensor, try a system restart)

4. Install Psensor

The latest Psensor 1.0.2 is available in its official Unstable PPA for Ubuntu 14.04 only for now (it will be available in the stable PPA after the new packaging is accepted into Debian).

To add the Psensor Unstable PPA and install the latest Psensor in Ubuntu 14.04, use the following commands:

sudo add-apt-repository ppa:jfi/psensor-unstable
sudo apt-get update
sudo apt-get install psensor

What stands behind each name in the list can be seen by going to Sensor preferences, and look at the info for 'Chip'.

Solution 2

There is not a real way of telling which temperature corresponds to which part of your computer, so a way could be guessing.

I took a look at an old post regarding SpeedFan which appears to show the same values of temperature like psensor. I guess these are the values of each hardware component:

Temp1 : Aux

Temp2 : Motherboard

Temp3 : CPU

Temp4: GPU

Solution 3

If I understand correctly the provided information, what you have named T2 in Psensor is coming from lm-sensors and AFAIK lmsensors does not monitor HDDs.

You can install hddtemp to monitor the temperature of your disk, Psensor will automaticaly display it.

The libatasmart is also supported by Psensor (>= 0.7.x).

PS: If you are not sure about the library used by Psensor to retrieve a given information, open the preferences of the sensor and look at its id field.

• id starting with 'lmsensor' => lm-sensors
• 'hdd ' => hddtemp daemon
• 'hdd at' => libatasmart
• 'nvidia ' => nvidia proprietary driver
• 'amd ' => ATI proprietary driver

Comments

[Admin]

thank you, a good guess would be ok, but in this case temp 1 and 4 are the highest and I guess they might refer to the CPU, while 3 is the lowest... that would be...what's the coolest main component? i know for a fact that my Intel Pentium M processor can go as high as 100 celsius

[dlin]

Your cpu has a usage of 11% which is very low so 35 Celcius seems acceptable.

[dlin]

My GPU which is old has the same temperature as yours, 65 Celcius so I think these values are correct :) As for the coolest main component, all are pretty hot even though they have fans.Your GPU may have the highest temp and usually the CPU temp should not be that high if you are not running a billion of processes. So I'd go with the CPU.

[dlin]

Temp1 should be AUX(Auxiliary) = false sensor reading

[Admin]

the 4th is the GPU, but cannot think that the cpu (the third) is the coolest (en.wikipedia.org/wiki/…)

[dlin]

his CPU has a usage of 11% so it's very normal to be under 40 C.

[Admin]

my point is that temp3 is always the coolest component. (can that be the processor? *computerhope.com/issues/ch000687.htm) mine is Intel(R) Pentium(R) M processor 2.13GHz (going up to 90 is normal) also, temp3 is not the one that goes up with cpu usage (temp1 does that - see the new image that I will add for psensor). stressing it a little bit more I can see that the only temperature that does not move is the third: that is not the cpu

[dlin]

then it would be Temp2 -> CPU Temp3 -> motherboard

[Admin]

my conclusion (see new image) is: T1 correlated to CPU use, T2 almost no variation, T3 no variation at all, T4 correlated to flash, T2 bigger than T3. CPU cannot be T2 nor T3 (it variates for sure). What is hotter, the motherboard or the HDD? i think is the mthb

[Admin]

my question was: "which is which" in psensor. i understand that T2 (originally temp2) in psensor is not the hdd temp. what is it? (in fact hddtemp is already installed so hdd temperature should be displayed in psensor). i was interested mainly in identifying the CPU and the GPU temperatures, which i did, i think. considering open the preferences of the sensor and look at its id field: how to do that? what do you mean by "sensor"? i thought that psensor is the one that tells the temperatures, but it seems that based on various sensors it may display different things. is this the case?

[JeanFI]

I understood your main question, but I have no glue, it is always quite painful to know which is which except for cpus when handled by the coretemp module because it requires to have the HW spec... My comment was just about the T2 that you have assigned to the HDD and I am quite sure it is wrong. Psensor does not retrieve by itself the temperature but use underlying libraries for this purpose. If you want to know which lib is used for a given sensor, left mouse click on its name in the table of the main window, select 'preferences', and take a look at the 'id' displayed field.

[Admin]

i have edited answer related to t2. but what about the fact that hddtemp is already installed so hdd temperature should be displayed in psensor? it is not? as for the 'preferences', and the 'id' displayed field: nothing much there:img856.imageshack.us/img856/1156/screenshotfrom2012090‌​61.png. the same imsensor for all

[JeanFI]

Yes it should, except of course if your particular hdd is not supported by hddtemp (in this case you may try the --use- libatasmart option) or does not have a temperature sensor. If your HDD is /dev/sda, try sudo hddtemp /dev/sda to check if it is ok at least on the hddtemp side.