Got proprietary Nvidia drivers installed by Ubuntu itself, graphic card is recognized well by the system yet brightness control does not work when adjusted by either FN + F5/6 shortcut or by dragging brightness slider manually (keyboard shortcut triggers slider move as well, so it's heard by the system).

However: xrandr | grep " connected" | cut -f1 -d " " produces single output DP-2 and xrandr --output DP-2 --brightness 0.7 does change the brightness.

Googled a lot, tried various options, neither works to me. What can I do to make it work when dragging the slider as well?

  • Do you by any chance have acpi=off or noacpi in your grub boot parameters, which would have the effect of disabling your FN+function key controls? – PJ Singh Jun 6 '20 at 16:34
  • Nope. Config is good and all the FNs are working. – Sereja Bogolubov Jun 6 '20 at 16:34
  • What does ls /sys/class/backlight reveal? On a laptop the hardware brightness is what FN keys control. Using xrandr is software control primarily used for external monitors not built in laptop displays. – WinEunuuchs2Unix Jun 6 '20 at 16:52
  • @WinEunuuchs2Unix acpi_video0. What does that mean? – Sereja Bogolubov Jun 6 '20 at 16:58
  • @SerejaBogolubov See if this helps: nvidia backlight brightness problem – WinEunuuchs2Unix Jun 6 '20 at 17:11

So, finally - after trying lots and lots of options - following helped me: At the /usr/share/X11/xorg.conf.d folder find file related to your nvidia and append following section:

Section "Device"
    Identifier "Device0"
    Driver "nvidia"
    VendorName "NVIDIA Corporation"
    BoardName "<your graphic card as it named in your system>"
    Option "RegistryDwords" "EnableBrightnessControl=1"

You can find the name of your graphic by searching for "system" in your Ubuntu. In my case it is GeForce GTX 1660 Ti so in abovementioned configuration file it gonna be BoardName "GeForce GTX 1660 Ti" - enclosed in doublequotes.

Save and reboot.

  • Thank you! That one worked for me. Btw it worked both with and without the BoardName line for me. – Guillaume Perrault-Archambault Nov 14 '20 at 3:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.