How to change lowest fan speed?

I am currently running Ubuntu 22.04 installed via oowow

The fan is very noisy even when in the lowest setting.
Is there a way to change the PWM output setting?

Yes, you can follow the step below.

Setup the fan to manual low speed mode.

fan.sh low

Chage the fan pwm level. The pwm level range is: 0x00~0x64, you can setup to a more lower speed,
e.g. 0x10

i2cset -y -f 6 0x18 0x8a 0x10
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There was always support for more precise fan control other than the 3 modes ?
quite astonished to see it wasn’t mentioned in the documentation :astonished:

I was looking at this too. Although that i2cset commands works fine for a while in mode auto, as soon as the threshold in /sys/class/fan/trigger_temp_low is reached, the fan speed again goes to the default value.

So a really nice change I’d request would be to be able to set the pwn level related to the trigger temperatures :slightly_smiling_face: !

Something for example like : echo 0x10 > /sys/class/fan/pwm_temp_low ?

This solution only works when I manually set fan.sh to low and does not work for auto mode.
I tried to change the settings in /usr/local/bin/fan.sh or /usr/local/bin/fan_setup.sh but I could not find any command similar to i2cset instruction as you suggested.

Is there any permanent solution for setting the pwm value as default?

Yes, it only works under auto mode.

https://docs.khadas.com/products/sbc/vim4/add-ons/cooling-fan#set-the-trigger-temperature

Yes, @numbqq, I understand, but to clarify: I would like to be able to set the exact fan speed which is used when low, mid, and high are triggered.

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