Thanks for the solution. But, for me it doesn't work somehow...

It only works if I delay systemd service startup:
ExecStartPre=/bin/sleep 0.9

In what way doesn’t it work?
amdgpu-fancontrol.path doesn’t trigger or amdgpu-fancontrol.service errors anyway?

amdgpu-fancontrol.path triggers amdgpu-fancontrol.service, so that's ok.

But I got this error: amdgpu-fancontrol[413]: invalid hwmon files
As you can see in the first ss:

Delayed service works fine...

Are you sure you also updated the .service file? Because that one should not be enabled. (Maybe it has to be manually disabled first)

Yes, I have updated the .service file. It was not enabled by default.

I enabled only .path file, located in /usr/lib/systemd/system/
sudo systemctl enable amdgpu-fancontrol.path

The .service unit can't be enabled.

The unit files have no installation config (WantedBy=, RequiredBy=, Also=,
Alias= settings in the [Install] section, and DefaultInstance= for template
units). This means they are not meant to be enabled using systemctl.

It says enabled in the Loaded: line for the .service unit in your screenshot though. Can you try to disable it?

Yes, it seems to be enabled, sorry. Ok, I disabled it and restarted the computer.

Here are the changes but fan speed is not changing at boot (.service is inactive):

If I restart the .path with sudo systemctl restart amdgpu-fancontrol.path, the fans starts spinning faster, pwm value becomes ~150.

150 is used just for testing.