Comment # 7 on bug 98333 from John Bridgman

The NVidia ticket suggests this might be an EDID issue, with the display saying
that it supports 4:2:2 at 4K/60 Hz when in fact it only supports 4:2:0.

Or could have been an NVidia driver bug that caused problems when modes for
both 4:2:2 and 4:2:0 were available, hard to say. Anyways, seems like if we can
get the driver to try 4:2:0 (possibly ignoring the monitor to do so) then it
should work at 60 Hz.