Fan speed regression with NVIDIA beta 470.42.01 and RTX 3080 (fans don't stop on idle)

edit: using Linux kernel 5.12.15 in both cases.

Using a 3080 with 465.31 sees a fan speed of 0% on idle.
With 470.42.01 the lowest is 30%.
Trying to change it does not work, everything above 30% works.

e.g:
works:
nvidia-settings -a "[gpu:0]/GPUFanControlState=1" -a "[fan:0]/GPUTargetFanSpeed=60" -a "[fan:1]/GPUTargetFanSpeed=60"

does not work:
nvidia-settings -a "[gpu:0]/GPUFanControlState=1" -a "[fan:0]/GPUTargetFanSpeed=0" -a "[fan:1]/GPUTargetFanSpeed=0"

Summary: on 465.31 without touching any settings the automatic fan control will shutdown the fans on idle, with 470.42.01 this is no longer the case.

This also doesn’t work on the new 470.57.02 release.

To even be able to change the fan speed (it seems), you need to create/add the following to “/etc/X11/Xwrapper.config”:

allowed_users=anybody
needs_root_rights=yes

Also set:

sudo chmod u+s /usr/lib/Xorg.wrap

Now X runs with root permissions, great…

Now you can do (e.g.):

nvidia-settings -a "[gpu:0]/GPUFanControlState=1" -a "[fan:0]/GPUTargetFanSpeed=60" -a "[fan:1]/GPUTargetFanSpeed=60"

But you can’t set it to anything below “30”, e.g:

nvidia-settings -a "[gpu:0]/GPUFanControlState=1" -a "[fan:0]/GPUTargetFanSpeed=21" -a "[fan:1]/GPUTargetFanSpeed=21"

or

nvidia-settings -a "[gpu:0]/GPUFanControlState=1" -a "[fan:0]/GPUTargetFanSpeed=0" -a "[fan:1]/GPUTargetFanSpeed=0"

will set fans to 30%.

tl;dr: The fans will never idle (0 RPM) and ALWAYS be set to AT LEAST 30%.

This issue does not happen under Wayland.
This issue does not happen on 465.31.