Ubuntu – Brightness fn key shortcut doesn’t work on ASUS laptop


The brightness shortcuts via fn key don't work.

I tried each solution from this answer and its comments. After editing /etc/default/grub file I rebooted.

GRUB_CMDLINE_LINUX="acpi_osi=linux acpi_backlight=vendor"

What other workarounds/solutions are there?

Relevant output:

$ sudo lshw -C display
  *-display UNCLAIMED     
       description: 3D controller
       product: GK107M [GeForce GT 750M]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a1
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list
       configuration: latency=0
       resources: memory:f6000000-f6ffffff memory:e0000000-efffffff memory:f0000000-f1ffffff ioport:e000(size=128) memory:f7000000-f707ffff
       description: VGA compatible controller
       product: 4th Gen Core Processor Integrated Graphics Controller
       vendor: Intel Corporation
       physical id: 2
       bus info: pci@0000:00:02.0
       version: 06
       width: 64 bits
       clock: 33MHz
       capabilities: msi pm vga_controller bus_master cap_list rom
       configuration: driver=i915 latency=0
       resources: irq:50 memory:f7400000-f77fffff memory:d0000000-dfffffff ioport:f000(size=64)

Best Answer

In the terminal:

  1. sudo nano /etc/default/grub




    GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi="

    Then, save the file.

  2. sudo update-grub

  3. Restart computer.

The function keys (Fn+F5/F6) should now be active.

I found out that the grub file got modified after an upgrade of the system and had to do it again.