Well, it is not a bug, but a change wrt to 3.8.x where I'm unsure whether it is wanted. The attached screen shot shows my external 1680x1050 VGA display, attached onto my notebook (closed LID w/ 1440x900 internal). In the past the console messages were not surrounded by the colourfull pixel area at the bottom and to the upper right corner - so just be informed about that.
Created attachment 101101 [details] screen shot
This commit in drm-intel-fixes (on it's way to linus + cc: stable) should fix this: commit 1ffc5289bfcf7f4c4e4213240bb4be68c48ce603 Author: Jani Nikula <jani.nikula@intel.com> Date: Tue May 7 18:54:05 2013 +0300 drm/i915: clear the stolen fb before resuming Thanks for reporting this bug and please reopen if this patch doesn't fix your bug.