The echo's Aaron Lu suggested did indeed adjust the brightness after trying them with root shell:
user@Qosmio-X75-A:/sys/class/backlight/intel_backlight$ sudo -s [sudo] password for user: root@Qosmio-X75-A:/sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight# ls actual_brightness brightness max_brightness subsystem uevent bl_power device power type root@Qosmio-X75-A:/sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight# cat max_brightness 5273 root@Qosmio-X75-A:/sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight# echo 400 > brightness root@Qosmio-X75-A:/sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight# echo 4000 > brightness root@Qosmio-X75-A:/sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight# You'll also notice that I've attached photos of the keyboard (in post#6), as I couldn't imagine how you'd implement the proper mappings without seeing the symbols shown on the keys themselves. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1295141 Title: Toshiba Qosmio X75-A7298 - Can't Adjust Brightness To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1295141/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs