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I've a Sumsung series 5 laptop with 4GB ram dual booted with Windows 10 and Ubuntu 16.04 LTS. My brightness does not work although the "function key+brightness button" shows the indication that it is being changed but brightness just does not really change. It works fine on Windows 10.
sudo gedit /usr/share/X11/xorg.conf.d/20-intel.conf
Section "Device" Identifier "card0" Driver "intel" Option "Backlight" "intel_backlight" BusID "PCI:0:2:0" EndSection
sudo gedit /etc/default/grub GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to GRUB_CMDLINE_LINUX_DEFAULT="quiet splash video.use_native_backlight=1"
Still the problem is there