I have a new Samsung 9 series laptop with Intel Ivy Bridge graphics and a dual Windows 8/Ubuntu 13.04 boot configuration. As soon I reach the login screen my graphics goes awry:
1) Black horizontal lines appear after a few seconds. They seem to be associated with bits of graphics rendered on the screen, and move around with them. They can leave a trace on the screen which persists for several minutes after a reboot.
2) At the top of the screen there are some lines a few pixels thick which flicker.
Edit: this is a known problem. See links in comments below.
However, if I start the system with nomodeset or noacpi, these problems do not occur. But this limits the operation of the laptop and the screen backlight no longer works.
I have installed intel-linux-graphics-installer and upgraded to the latest Intel drivers.