The way to get useful information out of the intel kernel driver is to add “drm.debug=0x04” to the kernel boot commandline, which will cause the kernel module to print out a bunch of modesetting debugging information. Since this problem goes back to boot with the plymouth splash screen, it's clearly a problem in the kernel module's modesetting.
It's very strange that it appears non-deterministic! -- [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 ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs