How to get display support for 3840x1600?

[markjayjones]

Hi All,

I have the NanoPC-T4 which has both HDMI and USB-Type-C DisplayPort 1.2 video output (I believe the NanoPi-M4 does not do video on the USB-Type-C port).

I've got a Dell U3818dw monitor which almost supports 4k, but not quite.

The maximum resolution is 3840x1600@60 Hz.

I've tried both the HDMI connector/driver and the USB-C (USB Type C) DisplayPort 1.2 support.

While both work up to 2560x1440 (1440p), the GUI monitor/display configuration does not offer a resolution above this. AUTO just picks 1440p.

Is there a way to get support for 3840x1600@60 Hz? The specs say this board supports 4k@60hz (which is 3840x2160@60Hz). I would think it could support a slightly lesser resolution as well.

Any suggestions?

- Mark

[markjayjones]

Got it working.

For someone else trying to figure this out with another odd resolution, check the /var/log/Xorg.0.log for your resolution. The monitor usually reports all resolutions they support, but the X server seems to only pick from a "suggested" list of resolutions. I searched /var/log/Xorg.0.log for 3840 and found this:

[ 9.009] (II) modeset(0): Modeline "3840x1600"x0.0 395.00 3840 3888 3920 4000 1600 1603 1613 1646 +hsync -vsync (98.8 kHz eP)


Based on the above (which is reported directly by the monitor) here are the commands to add the new resolution for me:

sudo xrandr --newmode "3840x1600_60.00" 395.00 3840 3888 3920 4000 1600 1603 1613 1646 +hsync -vsync
sudo xrandr --addmode HDMI-1 "3840x1600_60.00"

After doing this, just go into the system menu Preferences/Monitor Settings and choose the new 3840x1600_60.00 resolution under the HDMI-1 monitor.

Works great!

Does not seem to work for the DP-1 output (DisplayPort over USB Type-C), which seems limited to 1440p (2560x1440).

- Mark