I'm running dualboot Windows 10 and Ubuntu 18.04 (using the respin from this link). Everything works properly, however the fans are continuously going on and off. The CPU temp is between 39 - 42 degrees celsius. I think the fans are activated somewhere within this range, then cool the CPU and thus get the signal again to stop the fans, etc. On Windows, the fans are completely off at idle or light work.

What I already did

  • lm_sensors: cannot find the fans even after "sudo sensors-detect"

  • i8kutils: Cannot find /prod/i8k

  • BIOS updated to version 1.5.0

  • Kernel is version 4.19.2-041902-generic

  • Installed and activated thermald, tlp, powertop and intel-microcode.

  • Set the graphics card to Intel for power-saving

    • "sudo prime-select intel"
  • Undervolt by -140 mV on core and CPU, and -40 mV on iGPU (using this link)

  • Installed smbios-utils and set it to different modes (balanced, cool-bottom, quiet, performance)

  • Disable fan BIOS control (see link)

All without any luck.

What I still want to do

  • Repasting


sudo tlp stat

+++ System Info

System         = Dell Inc. XPS 15 9570
BIOS           = 1.5.0
Release        = Ubuntu 18.04.1 LTS
Kernel         = 4.19.2-041902-generic #201811132032 SMP Tue Nov 13 20:34:19 UTC 2018 x86_64
/proc/cmdline  = BOOT_IMAGE=/boot/vmlinuz-4.19.2-041902-generic root=UUID=5394fef0-92d3-4753-a6a1-fd7b5c4f9cea ro quiet splash quiet acpi_rev_override=1 acpi_osi=Linux scsi_mod.use_blk_mq=1 nouveau.modeset=0 nouveau.runpm=0 mem_sleep_default=deep vt.handoff=1
Init system    = systemd v237
Boot mode      = UEFI

+++ Temperatures
CPU temp               =    43 [°C]
Fan speed              = (not available)

I guess that Ubuntu is unable to see the fans and is thus unable to take control over them. Any suggestions to gain control over them?

4 Answers 4


I found a solution to my own problem.

To see the fans with lm_sensors

Add dell-smm-hwmon to modules:

sudo su
echo "options dell-smm-hwmon restricted=0 force=1" > /etc/modprobe.d/dell-smm-hwmon.conf
echo "dell-smm-hwmon" >> /etc/modules  # check manually before
sudo update-initramfs -u

Reboot, and the fans should be visible with:

Adapter: Virtual device
fan1:           0 RPM
fan2:           0 RPM

To take over control of your fans

Then follow this guide to install i8kutils:

sudo apt install i8kutils
sudo su 
echo "i8k" >> /etc/modules  # check manually before
echo "options i8k force=1" > /etc/modprobe.d/i8k.conf


sudo modprobe i8k force=1

Configure i8kutils:

sudo -H gedit /etc/i8kmon.conf

Finally, disable Dell BIOS Fan Control with this program by TomFreudenberg to let i8kutils take over.

git clone https://github.com/TomFreudenberg/dell-bios-fan-control.git
cd dell-bios-fan-control
sudo dell-bios-fan-control 0

Simply i8kmon service will be started and will control your fans. You can also disable i8kmon to try ik8fan to manually control your fans (not recommended as you might turn off your fans and they will never be started putting your CPU and GPU danger!).

i8kfan 2 2
  • What's inside your`/etc/i8kmon.conf file? When I try using the details I find in the blog post the fans start to work at double speed instead
    – amarchin
    Dec 26, 2018 at 23:20
  • I just used the default configuration file. There are only three modes available: off, low speed, high speed.
    – J. Ehrling
    Jan 13, 2019 at 19:55
  • Are the changes made by Dell BIOS Fan Control by TomFreudenberg written to the BIOS firmware ? I have a ubuntu/windows dual boot and would like to make sure that this linux configuration tweaks will not affect the fan control under windows. Thanks! EDIT: I meticulously applied all steps above and fans don't spin automatically when dell-bios-fan-control 0 is used, with i8kmon in daemon mode. My CPU temps went up to ~90°C while browsing the web and reading PDFs. Anything missing from this guide to make sure this works ?
    – remi
    Feb 26, 2019 at 14:48
  • 2
    If you use sudo in combination with >, the file redirection takes place in the context of the user, and you get permision denied errors
    – Ferrybig
    Jul 28, 2020 at 19:55
  • 1
    did you just make me empty my /etc/modules file? Oct 14, 2020 at 21:38

A less intrusive method to get less temperature (and therefore no fans are required) is using powertop.

 cat /sys/bus/pci/devices/0000\:01\:00.0/power/control # (on?. That is bad)
 sudo powertop --auto-tune
 cat /sys/bus/pci/devices/0000\:01\:00.0/power/control # (auto?. That is good)

In order to get the changes permanently, see How do I make Powertop changes permanent? . However, in the help of TLP it is said that 'attempting to apply powertop's --auto-tune settings on each boot will conflict with TLP'. By now, it is working fine for me (XPS 15 9570, bios 1.5).


My Dell 9570 (Intel i7-8750H) runing on Linux Mint 19.1 and Windows 10.

  • Bios version : 1.10.1
  • Kernel : 4.18.0-21

On Mint, after only repasting of CPU/GPU with Phobya NanoGreace Extreme, I obtain 42° C @Idle ** on "CPU Temperature Indicator" software monitoring. It gives me a gain of approximately -7° C @Idle, the benefit is even greater at full CPU load.

With add Powertop Intel software (available in the software manager), I obtain on my system only 34° C @Idle **, on average I am closer to 38° C.

Official web site : https://01.org/powertop/

First I have calibred Powertop for my sytem (calibration process taking a few minutes and making the computer partially unusable during this time), after this I have execute it.

sudo powertop --calibrate

sudo powertop --auto-tune

Look at the manual of powertop : https://www.systutorials.com/docs/linux/man/8-powertop/

For enable simply Powertop at system boot, I have making a cron fonction file on /etc/cron.d named powertop with right of execution enable containing this fonction :


@reboot root powertop --auto-tune

Dont use TLP at the same time, it would cause conflicts.

On Windows after repasting, the low temperature is 38° C @Idle **, on average I am closer to 42° C (on Intel Extreme Tuning Utility software) with Dell Power Manager calibrated to Optimized (standard) or Silence as needed. Dell Power Manager seems to me that he calibrated the bios with this value, this is satisfying for me. Optimized mode seems to the best setting for Linux.

I also realized some hardware optimizations : Opening the air vents (under the case at center of fans), adding two thermal pad (3 x 1 cm / 17 W/mK) on the CPU/GPU heat pipe, one on top left and one on top right just in front of fan.

I do not like undervolt my CPU because Linux does not seem to handle this well.

Through it all I earn approximately -15° C @Idle ** on Linux. My laptop has become very quiet and I am finally fully satisfied with it.

** best score

  • Did you ever try other suggestions like i8kutils? Jun 3, 2019 at 19:48
  • No, I dont use i8kutils. This is a old software in version 1.43 from 02.07.2017. I do not think it fits my Dell 9570. My system work fine, I do not want to make him unstable... Jun 3, 2019 at 21:46
  • I had all kinds of trouble with i8kutils causing machine to pause and videos to stutter when tlp in use. Jun 3, 2019 at 21:49
  • That does not surprise me than i8kutils causing problems. I do not use TLP either. I do not think it's desirable to have 2 optimization programs that work at the same time... This may create instabilities. Powertop work perfecttly. Jun 3, 2019 at 21:58

FWIW, below worked for me after wasting a bit of time:

sudo apt-get install ipmitool   # install
sudo ipmitool sdr type fan      # check fan speed
sudo ipmitool raw 0x30 0x30 0x01 0x00       # disable automatic control
sudo ipmitool raw 0x30 0x30 0x02 0xff 0x00  # set fan speed to 0x00

not sure if relevant but also disabled idrac -- ctrl+e during boot & disable services there. (you can safely ignore this if you are not using a server)

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