https://bugs.freedesktop.org/show_bug.cgi?id=75128
--- Comment #3 from publicface@bak.rr.com --- Created attachment 94252 --> https://bugs.freedesktop.org/attachment.cgi?id=94252&action=edit output of dmesg
Note that I do not have a screenprint for two reasons... 1) I've already restarted kdm as the artifacts make it impossible to read the screen and 2) for whatever reason my screenprint (ksnaphot) stopped working and I've been unable to determine why or how to fix it.