I am using Kubuntu with Ubuntu 14.04 and KDE 4.13.3 on a Lenovo Thinkpad (more specific spec below).
Since some time now I am getting extreme surges in fan speed that drop off immediately after.
Most of the time theses peaks in fan speed arise every couple of minutes. This even happens when completely idle. When under heavy load the intervals narrow, but the CPU fan speed is still pulsing up and down. I captured some data on this using Psensor which might illustrate the problem:
Idle behavior
Fan speed (green), CPU temp (blue):
Heavy load
Six Cores running on 100% running infinite loops in python; Fan speed (green), CPU temp (blue). Heavy load interval is marked with a red circle:
This overshoots in the fan speed create a really unpleasant soundscape. Is there a way to prevent these peaks from happening? I would prefer a solution that works without any additional software, but I am up for anything.
Edit:
I tried changing the Adaptive Thermal Management Scheme to Balanced, as suggested in this similar question, but this did not solve my problem. The fan speed still behaves as shown above.
Hardware:
- ThinkPad T540p
- CPU: Intel(R) Core(TM) i7-4710MQ CPU @ 2.50GHz
Firmware:
- UEFI BIOS Version GMET69WW (2.17) (Newest version is 2.23, but none of the newer version mentions any changes to fan behavior in the changelogs)
Software:
- Ubuntu 14.04
- KDE 4.13.3
Problem persists with
- Ubuntu 16.04
- KDE 5.5.5
Windows users also complain about this. This laptop uses the Intel Q87 express chipset which does not have PWM outputs so the only way of controlling the fan speed is via the BIOS. You could try changing the power management profile to balanced.
I do not recommend removing dust by using an air duster to blow the dust into the laptop. It is much safer to use a domestic vacuum cleaner to suck dust out, although this is nothing like as effective at cleaning the fan as disassembly and using something like a glass cleaning wipe on the fan blades.