Questions[fancontrol](ubuntu)

The situation

I switched an old Imac (2008) to Lubuntu. While it runs smoothly for all I need to do, 20 minutes after starting the CPU fan starts to get super loud. Here is a screenshot of psensor: psensor screenshot psensor screenshot

Basically, 2 sensors, TD0D and temp1 see an increase in temperature until reaching 105°C, which triggers the increase of the CPU fan speed. This fan gradually accelerate until its max, 3600 RPM, which makes the imac very loud. This do lower the temp of these 2 sensors, until aournd 80°C, but this is not cool enough to reduce the fan speed.

This is annoying because I think with a fix speed set to 2000 RPM for example, the temp would stabilise at an acceptable temperature, hopefully below 90°C, while the noise would still be acceptable.

What I tried so far

I tried to follow the steps described here: How to control fan speed?, so basically set up lm-sensors, then set up fancontrol with the help of pwmconfig But pwmconfig answers: There are no pwm-capable sensor modules installed Even after adding the module applesmc to /etc/modules and rebooting, no chance.

I also tried to install mbpfan: https://github.com/linux-on-mac/mbpfan But it is meant for macbooks and not for imacs, with the result that only one sensor seems to be taken into account, then all fan speed are raised simultaneously, which is not helping in my case (see https://github.com/linux-on-mac/mbpfan/issues/211)

What I think could work but not sure how

pwmconfig is "just" a helper to create the fancontrol settings file. So I could simply make this settings file myself and set up a min speed of 200 RPM for the CPU fan. But I am not sure this can work, because maybe fancontrol can only control PWM fans and somehow imac fans are not PWM. Also, if it can work, I am unsure what should be the path of each fan to put in that file and whre I could find an example of settings file.

So: can fancontrol work? if not, do you have any other ideas?

Actually, I realise the problem seem to come from the GPU, since temp1 seems to be in the Radeon PCI section. My imac has a Radeon RV630 Graphic Card. Could it be that there is a better driver somewhere that would lead to it heating less? This is happening while browsing internet or even not doing anything, so it's not linked to complex graphics calculations...

here is the output of sensors if that helps

applesmc-isa-0300
Adapter: ISA adapter
ODD :         698 RPM  (min =  700 RPM, max = 4800 RPM)
HDD :        1229 RPM  (min = 1200 RPM, max = 5900 RPM)
CPU :        3602 RPM  (min = 1200 RPM, max = 3600 RPM)
TA0P:         +27.8°C  
TC0D:         +50.5°C  
TC0H:         +49.8°C  
TC0P:         +50.0°C  
TG0D:         +78.8°C  
TG0H:         +66.2°C  
TG0P:         +71.0°C  
TH0P:         +57.8°C  
TL0P:         +58.0°C  
TO0P:         +49.8°C  
ERROR: Can't get value of subfeature temp11_input: I/O error
TW0P:             N/A  
Tm0P:         +53.2°C  
Tp0P:         +82.8°C  

radeon-pci-0100
Adapter: PCI adapter
temp1:        +80.0°C  

coretemp-isa-0000
Adapter: ISA adapter
Core 0:       +49.0°C  (high = +105.0°C, crit = +105.0°C)
Core 1:       +59.0°C  (high = +105.0°C, crit = +105.0°C)

Thanks a lot for the help!

On my Lenovo Yoga 730-15IWL with a i5-8265U CPU, the sensors-detect command cannot detect the fans, so sensors cannot show them either.

How can I show the fans speed on such a system?

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?

it's days that the fan and especially the processor of my computer are perennially 100% even if there is no real reason.

This is the situation

Can someone help me?

This is htop with Chrome close

I did a fresh install of Ubuntu 18.04, alongside Windows 10. On Ubuntu, one of my fans is extremely high, although the temperature is fine, and this is not happening on Windows. I've tried some of the solutions suggested in this forum, without success.

The one with the problem seems to be nct6775/fan2, at least it is the only one working at +1155 rpm, according to program HardInfo. My motherboard is an ASUS H81M-A.