I tried this diff and at least one thing changed -- neverball now works
(previously it immediately hung the GPU on start). There is still
corruption and GPU hanging in chromium. There is corruption in mplayer
-vo gl too (and it is still much slower than it is on 5.4).
With a lot of help from Stefan Sperling I tried to do experiments.
Since I am too unskilled I was not able to do it properly and build
xenocara from the same point in time (date-based CVS checkouts do not
compile for me) but I built kernel on 5.3 from 2013-07-06 with just this
patch applied:
http://freshbsd.org/commit/openbsd/304417ea27d0874895cc4e65c30324b7bd14ac22 (as I am 80% sure it's when problems started) and the screen became totally corrupted in X but computer did not hang. It looked very similar to what is seen now. If that helps that is all I could find out.
