I am trying to work out how to add a 2560x1400 mode to the ViewSonic 32"  2560x1440 (16:9) display configuration that is not listed on the display settings configuration and should be there.

 

Any tips on updating the configuration file, locally and then as a patch to Armbian please ?

9 часов назад, AaronNGray сказал:

a 2560x1400 mode to the ViewSonic 32"  2560x1440 (16:9) display

Perhaps the problem is not in the configuration file.
Provide more information about the OS such as:

uname -r
 
awk '{gsub(/ /, "\n\t", $0); print "\n\t" $0 "\n"}' /proc/cmdline

dmesg | egrep -i 'drm|hdmi|gpu|model'

And anything else that seems suspicious to you.