Ubuntu
xserver-xorg-video-intel package

  1. Bug #557436
  2. Comment #21

Comment 21 for bug 557436

Revision history for this message
Chris Halse Rogers (raof) wrote : Re: [Bug 557436] Re: [GM45] [upgrade] [regression] [lucid]: external monitor only usable via DVI, not via DP

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!