I recently updated to ubuntu 13.04 and needed to change the brightness because i was getting a blank screen on login. FN+UP temporarily fixed this.
i entered the following in /etc/default/grub
and that fixed the blank screen problem but now i can change the brightness. how can i make it so i can change the brightness settings again?Code:GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=linux acpi_backlight=vendor"