This issue seems related to lp:1405349, not sure if it is the same root- cause.
** Description changed: Steps: - 1. Suspend the computer by pressing the Sleep key + 1. Suspend the computer by pressing the Sleep key(Fn+F2 on the keyboard here) 2. Press any key on the keyboard or the Power button to wake the device up Expected results: 1. The system suspends and the Power button LED blinks 2. The system wakes up and user can log in. Actual results: 1. The system suspends and the Power button LED blinks (OK) 2. The login screen appears and the screen is immediately turned off (NOK). User needs to move the mouse or enter a key to turn the screen on. Additional information: - In a few additional occasions, after performing this action several times (pressing the Sleep key to suspend the system, then wake it up), the system freezes at log in screen just before going to suspend mode. It has to be force-stopped and restarted. - Please note that this problem does NOT happen when suspending from the User Menu or using the Power button and selecting Suspend. ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: lightdm 1.10.4-0ubuntu2 ProcVersionSignature: Ubuntu 3.13.0-34.60-generic 3.13.11.4 Uname: Linux 3.13.0-34-generic x86_64 ApportVersion: 2.14.1-0ubuntu3.7 Architecture: amd64 Date: Thu Mar 12 11:19:32 2015 DistributionChannelDescriptor: # This is a distribution channel descriptor # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor canonical-oem-stella-datong140729-kylin-trusty-amd64-20150205-2 InstallationDate: Installed on 2015-02-10 (29 days ago) InstallationMedia: Ubuntu 14.04 "Trusty" - Build amd64 LIVE Binary 20150205-07:08 LightdmConfig: [SeatDefaults] autologin-guest=false autologin-user-timeout=0 autologin-session=lightdm-autologin #autologin-user=u SourcePackage: lightdm UpgradeStatus: No upgrade log present (probably fresh install) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1431128 Title: screen remains blank after waking up from suspend To manage notifications about this bug go to: https://bugs.launchpad.net/oem-priority/+bug/1431128/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs