I've managed to solve my own bug (#10545) by applying the following
patch to the xserver.
Please apply.
<Conspiracy mode on>
This monitor is "Vista Certified". I wonder if this is a pure coincidence...
<Conspiracy mode off>
With kind regards
Erik Andrén
(cherry picked from commit a63704f14a1d97b9a00fef6fa290e74e51b9732b)