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
Stats
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?