I had the exact same problem as Will describes with an Asus eeepc 1001P and his fix in comment #8 worked.
-- 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
