Originally Posted by JaXXoN
T221 has a maximum refresh rate of 41 Hz
Just recognized that there are different models - there's also one with 48 Hz.
So 246 MHz might do it.
BTW.: just recognized from the modeline that the horizontal total is 4160
pixel, which exceeds the limit of the corresponding EDID field (4095), so
you for sure need to create an xorg.conf (changing the default EDID won't
help in your case despite told otherwise, before).