Hiho.. So whats the point about your actual problem:
Did you updated your BIOS or so ? I recently switched to debian back again. Because these same strange things used to happen under gentoo too. Thought it had something to do with the patchtree they are aplyiing to their sources. You might want to take a look at the corresponding gentoo-forum thread (more than 28 pages): http://forums.gentoo.org/viewtopic-t-198023-highlight-lockups.html But that puts the whole case under another light. ingo