How do i change coolbits?

I would like to change coolbits so i can control fan speed so my gpu doesent hit 100c while playing roblox but I get this when i try to

sudo nvidia-xconfig -a --cool-bits=28 --allow-empty-initial-configuration

WARNING: Unable to locate/open X configuration file.

Option “AllowEmptyInitialConfiguration” “True” added to Screen “Screen0”.
New X configuration file written to ‘/etc/X11/xorg.conf’

On Manjaro with nvidia, /etc/X11/xorg.conf is not used. The file is /etc/X11/mhwd.d/nvidia.conf