If your brightness slider and FN keys for brightness controller does not work on Linux then you can follow this simple guide to resolve this issue. The possible reason could be because your system have an Nvidia GPU, causing the system to not properly detect correct settings. Let's try to resolve this issue.
♦ Preliminaries
Update your system by running the following commands and reboot.NOTE: below command will update and install some dependencies for your system and reboot it.
sudo dnf update
# for debian based systems
# sudo apt-get update sudo dnf upgrade
# for debian based systems
# sudo apt-get upgrade
reboot♦ First Solution
This solution worked for me as I have NVIDIA GPU. Make sure you have NVIDIA drivers installed. You can verify this by following my guide on Installing NVIDIA drivers. After verifying (or installing drivers) continue to follow below steps.
Go to the directory '/usr/share/X11/xorg.conf.d'
cd /usr/share/X11/xorg.conf.d
sudo nano 80-nvidia.confAdd below code in the file, save and reboot the system
Section "Device"
Identifier "Device0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "GeForce RTX 2060"
Option "RegistryDwords" "EnableBrightnessControl=1"
EndSectionrebootThis fixed the issue for me. If your brightness slider still not working, you can try Second Solution.
♦ Second Solution
There is another solution to try that usually
fixes this. Open '/etc/default/grub' in
your favorite editor. Find the
line that starts with
'GRUB_CMDLINE_LINUX'and append
one of the below lines. One of these should work for you.
acpi_backlight=videoacpi_backlight=vendoracpi_backlight=nativeacpi_backlight=none
Example for reference
Important: After editing '/etc/default/grub' file, please run the below command and reboot.
sudo grub2-mkconfig -o /boot/grub2/grub.cfgrebootCongratulations! You should have successfully resolved the issue.
Leave a comment below if you have any question or suggestions.
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