system deadlock after hiberbate wake up

[Zippo]

above behavior is 100% reproducible since new installation of Ubuntu 14.04 (no upgrade from 12.04).
After hibernate wake up the screen displayed looks like a distorted chess game with black and white areas no coloured areas visible.
Trying to open a console does not work! Mouse and keyboard actions show no response. Only the power off switch is still working!
In 12.04 I had no such problems with the same hardware.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: lightdm 1.10.5-0ubuntu1
ProcVersionSignature: Ubuntu 3.16.0-34.47~14.04.1-generic 3.16.7-ckt8
Uname: Linux 3.16.0-34-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.10
Architecture: amd64
CurrentDesktop: Unity
Date: Thu Apr 23 18:50:52 2015
InstallationDate: Installed on 2015-03-26 (28 days ago)
InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1)
SourcePackage: lightdm
UpgradeStatus: No upgrade log present (probably fresh install)