I have had the same issue, adding Option "LVDSBiosNativeMode" "false" to the Device section of xorg.conf, solved the problem for me.
-- Xorg ATI driver somewhat supports ATI Radeon IGP https://bugs.launchpad.net/bugs/155954 You received this bug notification because you are a member of Ubuntu Bugs, which is the bug contact for Ubuntu. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
