OK, back working, but it's unclear why. The dmesg diff is about different timing, clock calibration, device detection order, and hence omitted.
I see the allocated screen in Xorg.0.log is now much smaller, and gdm already enables the cloned display; there's also a related xrandr difference. I tried booting with i915.modeset=0 which made matters worse, in that the DP outputs were no longer detected at all and prior to mode switching there was garbage, and screen flicker on reboots between linux kernel shutting down and the BIOS reinitializing the gfx chip. What I also did in between was: # gconftool-2 --recursive-unset /apps/gnome_settings_daemon/xrandr /apps/gnome_settings_daemon/plugins/xrandr /apps/gdm/simple-greeter /settings-manager-plugins/xrandr Current state: gconftool-2 -a /apps/gnome_settings_daemon/xrandr show_notification_icon = true gconftool-2 -a /apps/gnome_settings_daemon/plugins/xrandr priority = 1 active = true gconftool-2 -a /apps/gdm/simple-greeter/settings-manager-plugins/xrandr priority = 1 active = true Which parts of the overall system would save state from previous (possibly undocked) boots that might spoil the next startup? ** Attachment added: "differences in logging between previous non-working (-) and current working configuration (+)" http://launchpadlibrarian.net/46616300/changes.txt -- [GM45] [upgrade] [regression] [lucid]: external monitor only usable via DVI, not via DP https://bugs.launchpad.net/bugs/557436 You received this bug notification because you are a member of Ubuntu Bugs, which is a direct subscriber. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
