Ok, then perhaps it is a GPU lockup. Next time it happens, ssh in and collect the output of 'dmesg' and your /sys/kernel/debug/dri/0/i915_error_state file. Both of these must be collected while the machine is locked up (e.g. by sshing into the sick machine over ethernet). See https://wiki.ubuntu.com/X/Troubleshooting/Freeze for additional info.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/975848 Title: Black screen after screen lock To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/975848/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
