On Tue, Nov 08, 2016 at 11:00:20AM +0000, Barak A. Pearlmutter wrote:
> I have three monitors, two 4K and one 1920x1200, all lined up
> horizontally: [4k][4k][1920x1200]. This configuration worked fine
> until I upgraded to stretch (testing) a few weeks ago. Now only the two
> 4k monitors are usable, the third is off (by default) or if I force it
> on using xrandr it just mirrors.
>
> When I run xrandr it reports a maximum horizontal resolution of
>
> $ xrandr | head -1
> Screen 0: minimum 320 x 200, current 7680 x 2160, maximum 8192 x 8192
>
> 8192. But I need at least
>
> $ xrandr | egrep ' connected' | sed 's:^.* \([0-9][0-9]*\)x.*$:\1:' | awk
> '{t += $1} END {print t}'
> 9600
>
> 9600.
The X server may need a little more explicit configuration:
SubSection "Display"
Virtual 9600 2400
EndSubSection
-dsr-
