XPS 13 graphics problem when using KDE on 12.04

[Karlheinz Salver]

 XPS13 9993 UBUNTU problem with Graphics under KDE

after installing KDE ( apt-get install kubuntu-desktop)

there is a problem with the intel graphics.

the display shows different vertical lines like |||| |||| |||| .

sometimes these lines are suddenly on a black background, and the kde cannot be used.

After reboot, the screen resolution cannot be changed asn is default 1920x1025 ; in KDE and GNOME Unity).
my kernel version is 3.5.x

with KDE i've selected the "lightdm".
at a secondary test after a complete new installation , i changed under lightdm to use the unity-greeter:
same problem.

how I can resolve this problem?

[Karlheinz Salver (ksalver)]

additional i will test to add a

sleep 2

before the greeter will be started.
the results will be posted until 2014-07-14

[Karlheinz Salver (ksalver)]

ater adding

sleep 2

KDE worked without Problems