Comment 9 for bug 569879

I sometimes experience a similar problem, although I have an nVidia graphics card. The stack in the attached KDM log appears close, but not exactly the same, as the one posted in #5.

For me, this seems to be proceeded by my up key no longer working in KDE. If I then logout, I get a blank black screen and cannot do anything locally (no VT switching, etc). I don't get anything displayed the way others have described (messages, cursors, etc). However, I can SSH in and restart KDM to restore it.