My laptop is Samsung NP-Q430-JS03US.
I have searched for the solution. I have tried editing grub acpi_osi=Linux and acpi_backlight=vendor, but still didn't work.
on 02/08/2013 – Made popular on 02/08/2013
My laptop is Dell Inspiron n5010 with Linux Mint. Whenever i tried to adjust the screen brightness the laptop got stuck and nothing works after that until i force restart the system. I tried to make some changes in the 'grub' file (GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor acpi_osi=Linux") & updated grub(sudo update-grub) after some research, but that didn't help me.