ISSUE: Backlight brightness does not change. More Detail: Brightness will not change, using both 'System Settings-Screen', or FN keys (Brightness bar shows and moves, but screen brightness does not change). Notcied a post in this thread (http://ubuntuforums.org/showthread.php?t=1866283) about having multiple folders in Sys-Class-Backlight... I HAVE TWO FOLDERS TOO! 'intel_backlight' and 'acpi_video0' Using the function keys, alters the value in the acpi_video0's 'Brightness' file - But doesn't actually alter the brightness of the screen. If I add 'backlight=vendor' in Grub, my function keys then edit the value in the 'Intel_Backlight brightness file. - But again doesnt actually change the brightness of the screen. Computer: Fujitsu Siemans Pi2515, Intel Integrated Graphics, No hdd partition. Already Tried: -Editing grub to contain: acpi_osi=Linux acpi_backlight=vendor -http://ubuntuguide.net/change-screen-brightness-with-fn-key-in-ubuntu-11-0410-10 -sudo apt-get install acpi -$ sudo setpci -s 00:02.0 F4.B=20 -Brightness does not adjust in fallback mode either. -Reinstalling OS, Using Linux Mint (Same problem). -Upgrading and downgrading BIOS. Many thanks for reading, I understand this problem may need a bit of a Linux pro to sort. If anyones up for the challenge i'll spend any amount of time being walked through this, posting results. Don't want to give up here!