Just for reference - my xorg.conf
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My OpenPOWER (Raptor Blackbird) machine uses an internal framebuffer.
to drive the monitor This thing is known to have a bug which prevents.
it from autodetecting screen resolution. So it always run at 1280x1024.
To make it work one has to set up the "xorg.conf" file (on my Fedora it
is the "/etc/X11/xorg.conf.d/21-gpu-driver.conf" and it looks like
this: