Further tests of versions of kernels 3.11 and 3.13, and Xstacks saucy and trusty on 12.04 showed only black screens. => Now saucy too !!
But I've found a workaround for my config/setup (12.04 with kernel and Xstack from trusty with nvidia driver, lightdm with kde, and only hibernate used); Boot your system to lightdm, then login to your Desktop Environment , let it finish ... After that logout back to lightdm screen and login again ! => Now try to hibernate, after the resume there is no black screen anymore and you can unlock the screen and use your desktop!! My résumé after testing is that maybe there is a race condition in the services/daemons (acpid, dbus, lightdm) or different bugs are playing together (Kernel, X, drivers, daemons). That's why I've downgraded lightdm's version in 12.04, but without success, only the workaround, described above, helps for me. Please help to solve this nasty bug, because it is now in 12.04 too ! Maybe lightdm changes? Or system components like dbus? => Browsing the lightdm versions in 12.04 lightdm (1.2.3-0ubuntu2.4) precise-proposed; urgency=low [ Robert Ancell ] * debian/patches/06_config_directory.patch: - Backport conf.d configuration support (LP: #1190425) [ Alberto Milone ] * debian/patches/07_add_display-stopped-script.patch: - Backport support for the display-stopped-script entry in the configuration file (LP: #1259237) -- Alberto Milone <email address hidden> Wed, 18 Dec 2013 14:31:49 +0100 lightdm (1.2.3-0ubuntu2.3) precise; urgency=low * debian/guest-account: disable screen locking in a more reliable way. Rather than trying to write a key for another user, while setting up the guest user account, just set up an autostart desktop that will set it during the login (lp: #951000) -- Sebastien Bacher <email address hidden> Mon, 08 Jul 2013 13:47:53 +0200 Thanks, Bernhard -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1283938 Title: [Samsung NP535U4X-S01TH] Ubuntu 14.04 blank screen after wakeup from sleep To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1283938/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs