ubuntu acer notebook brightness not work

    If you use ubuntu with acer notebook, and you fint that you can't change brightness using hotkey. Hot to solve it?

First edit the file, "/etc/default/grub". Add "acpi_osi=Linux acpi_backlight=vendor" to GRUB_CMDLINE_LINUX_DEFAULT. So the setting should look like below.

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux               acpi_backlight=vendor"

After saving the file, you should type the below command. And reboot.

sudo update-grub

Now you should change brightness using hotkey.