I think it is needed some logs, kernel versions, etc.
florin@florin-Satellite-C650:~$ uname -a Linux florin-Satellite-C650 3.2.0-24-generic #37-Ubuntu SMP Wed Apr 25 08:43:22 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1001908 Title: Login screen doesn't always appear To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1001908/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs