The "screen suddenly goes blank" issue and the underruns are probably related, since the pipe will eventually just stop sending data if it gets too many underruns. This looks very similar to the issue in upstream https://bugs.freedesktop.org/show_bug.cgi?id=19304, there's a patch available for testing in https://bugs.freedesktop.org/attachment.cgi?id=24375.
** Bug watch added: freedesktop.org Bugzilla #19304 https://bugs.freedesktop.org/show_bug.cgi?id=19304 ** Changed in: xserver-xorg-video-intel (Ubuntu) Status: Incomplete => Confirmed -- [i855] Xorg errors and warnings for intel 855GM https://bugs.launchpad.net/bugs/304981 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs