Comment 4 for bug 543045

I see corruption on X1400 with external VGA screen (Thinkpad T60), possibly the same issue? The corruption looks like every other line is offset by a few (up to 10 or so) pixels, like a badly interlaced movie, and the amount of offset moves in waves. For me, this is fixed by changing (in Display Settings / xrandr) to the internal screen and then back. The display is then fine until next reboot.

I tried setting radeon.new_pll=0; this did not fix the issue, but it changed the appearance of the corruption somewhat (smaller offset perhaps? And no longer every second line, but maybe two and two lines).