Ask Your Question

Revision history [back]

click to hide/show revision 1
initial version

How to change CPU temperature thresholds?

My laptop fan max RPM is ~3100. Currently it usually runs at almost 2000 RPM maintaining temperature of as low as ~36 deg C.

How do I change the current thermal thresholds or add new ones?

Fedora 19
Thinkpad T500 with most recent BIOS

click to hide/show revision 2
lots of details on my findings so far

How to change CPU temperature thresholds?

My laptop fan max RPM is ~3100. Currently it usually runs at almost 2000 RPM maintaining temperature of as low as ~36 deg C.

How do I change the current thermal thresholds or add new ones?

Fedora 19
Thinkpad T500 with most recent BIOS

EDIT: Following the TLP trail (its output on its status) I've discovered the following contents of two files

cat /proc/acpi/ibm/thermal
temperatures:   39 36 37 -1 -128 -128 -128 -128 36 38 38 -128 -128 -128 -128 -128

cat /proc/acpi/ibm/fan
status:     enabled
speed:      1986
level:      auto

I thought it will be enough to just change these to whatever I like and be done with it. It turned out this files contain continuously updated readings from sensors, not settings! This can be verified by issuing watch cat /proc/acpi/ibm/fan

I've managed to gain manual control over my laptop fan following these instructions: How to control thinkpad_acpi but this doesn't solve anything.

Now, I know there are fan control scripts but I would really like to be done with changing just the threshold. It would also be great to provide a method not specific to a laptop model.

Note:
the /proc/... locations are specific to laptop models!

Note2:
I've set the fan to absolute max RPM for testing. It operated at 4700 RPM and managed to cool down my CPU to ~33 degrees. Now you see how idiotic it was to set the default threshold (Lenovo, kernel blokes...?!) to ~36 degrees. It's barely 10 degrees over room temperature!!!

How to change CPU temperature thresholds?thresholds and control fan speed?

My laptop fan max RPM is ~3100. Currently it usually runs at almost 2000 RPM maintaining temperature of as low as ~36 deg C.

How do I change the current thermal thresholds or add new ones?

Fedora 19
Thinkpad T500 with most recent BIOS

EDIT: Following the TLP trail (its output on its status) I've discovered the following contents of two files

cat /proc/acpi/ibm/thermal
temperatures:   39 36 37 -1 -128 -128 -128 -128 36 38 38 -128 -128 -128 -128 -128

cat /proc/acpi/ibm/fan
status:     enabled
speed:      1986
level:      auto

I thought it will be enough to just change these to whatever I like and be done with it. It turned out this files contain continuously updated readings from sensors, not settings! This can be verified by issuing watch cat /proc/acpi/ibm/fan

I've managed to gain manual control over my laptop fan following these instructions: How to control thinkpad_acpi but this doesn't solve anything.

Now, I know there are fan control scripts but I would really like to be done with changing just the threshold. It would also be great to provide a method not specific to a laptop model.

Note:
the /proc/... locations are specific to laptop models!

Note2:
I've set the fan to absolute max RPM for testing. It operated at 4700 RPM and managed to cool down my CPU to ~33 degrees. Now you see how idiotic it was to set the default threshold (Lenovo, kernel blokes...?!) to ~36 degrees. It's barely 10 degrees over room temperature!!!