Problem solved. Tried adding acpi_backlight=vendor to boot parameter. Did not work
So I tried the recommendation for Intel HD Graphic Controllers. Created the file /usr/share/X11/xorg.conf.d/80-backlight.conf with below contents as recommended. Section "Device" Identifier "Intel Graphics" Driver "intel" Option "AccelMethod" "sna" Option "Backlight" "intel_backlight" # use your backlight that works here BusID "PCI:0:2:0" EndSection Problem Solved. I am still running the upstream kernel at this time. Will reboot into the final release kernel and report as to whether this works in that kernel as well. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1307064 Title: Ubuntu 14.04 Beta cannot adjust brightness on Lenovo Ideapad Z570 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1307064/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs