Linux Troubleshooting

[ejr....@gmail.com]

Okay, I was having some issues getting dual input mode working (4k@120hz) with linux but I've figured it out. Posting this here for anyone who uses linux and runs into trouble, it's a little quirky. I'm on xrandr 1.5 which has some updates for tiled displays iirc.

buttons are: led screw brightness+ brightness- 4k@120hz 1080p@240hz 720p@340hz 480p@480 backlight screw

I had to do this in a specific order otherwise I would glitch out. switch to 4k@120hz from one of the other resolutions. set the left panel (DisplayPort-1 for me) to 1920x2160 even if it already is, disable the right panel (DisplayPort-2) and then turn the right panel back on by setting the resolution. the right panel will be cloned so you need to set it to the right of DP-1. I haven't tried a gui like arandr and I don't use nvidia, so this might be an amd only thing. here's the commands though

xrandr --output DisplayPort-1 --mode 1920x2160

xrandr --output DisplayPort-2 --off

xrandr --output DisplayPort-2 --mode 1920x2160 --right-of DisplayPort-1

no need for --refresh 120.

also X doesn't seem to have a concept of a "monitor", only separate panels. you can't fullscreen a window across both panels like this. the solution is to run i3 with fake_outputs or this handy workaround someone made:

https://github.com/CyberShadow/hax11

some extra info on linux tiled display support:

https://devtalk.nvidia.com/default/topic/982568/linux/-feature-request-proper-support-of-tiled-displays-4k-5k-etc-in-linux/2

[ejr....@gmail.com]

actually you can do this now with xrandr 1.5 (and maybe only i3) to join panels into a monitor:

xrandr --setmonitor ZisWorksX39 auto DisplayPort-1,DisplayPort-2

[ejr....@gmail.com]

another linux specific issue I've ran into is firefox not detecting the refresh rate properly or a vsync issue where it forces 60hz, this happened on my other 120hz monitors.

under about:config change layout.frame_rate from -1 to 120

[ZisWorks]

Thanks for posting these updates.

[rob...@swiecki.net]

Just got mine x28 (9 days to Europe, including 6 days here in CH;). Works well! I asked Zis not to include the power supply, and bought something locally (https://shop.boxtec.ch/adapter-12v10a-p-42313.html) to avoid import/CE problems.

Some early things i noticed with Linux.

My nvidia-390.25 + randr-1.5.1 + gnome-control-center-3.26.2 seem to recognize TiledID well, treating Zis28 as one display. All works (including alignment of display) well with all tested resolutions.

There's some problem with 4k120Hz, where initially both sides of the screen don't want to synchronize properly (dropped frames info on screen and the displayed picture is "jumping" every second or so). What helps is to switch to 4k60 and back to 4k120. I was initially thinking it's related to which DisplayPorts of my card (GTX 1080Ti) I use, but it seems to happen with all port configurations. My FW is V29.

There are typical problems with games like CSGO, which tend to start on my second monitor (no matter what's my primary monitor). What helps is to change CSGO video mode to windowed, move to ZisDisplay, and make it full-screen again.

The gnome-panel displays only on one side of TiledID screen, seems it might not yet understand new concepts of xrandr (monitors vs screens?).

Sometimes (rarely) when switching mode the displayed picture is incorrect, as in, it seems to display every second vertical line (as far as I can tell). But it's rare, and switching resolutions help.

My current xrandr settings (DP-0 is my Acer XB321HK)

$ xrandr -q

Screen 0: minimum 8 x 8, current 7680 x 2160, maximum 32767 x 32767

HDMI-0 disconnected (normal left inverted right x axis y axis)

DP-0 connected 3840x2160+3840+0 (normal left inverted right x axis y axis) 708mm x 399mm

   3840x2160     60.00*+  29.98    24.00  

   1024x768      60.00  

   800x600       60.32  

   640x480       59.94  

DP-1 disconnected (normal left inverted right x axis y axis)

DP-2 connected 1920x2160+1920+0 (normal left inverted right x axis y axis) 310mm x 341mm

   1920x2160    120.00*+  60.00  

DP-3 disconnected (normal left inverted right x axis y axis)

DP-4 connected primary 1920x2160+0+0 (normal left inverted right x axis y axis) 310mm x 341mm

   1920x2160    120.00*+  60.00  

DP-5 disconnected (normal left inverted right x axis y axis)

[ZisWorks]

Just to add to this thread, installed ubuntu 20.04 LTS on a system with a quadro rtx 5000. After install was done, plugged in an x28 and it fired up in dual input mode first time, properly merged halves and everything. Resume from sleep works too. A surprisingly plesant experience. Default drivers used, will load proprietary ubuntu blobs later.

quadro rtx5000 seems picky about dp ports

[Arthur Moraes Do Lago]

Hi, Im kinda late, but just wanted to add that I usually have problems when using multiple monitors in linux. For example, when plugging 4k120 + another monitor, I get a lot of flickering, and have to play with the settings in nvidia-settings(usually just aplying anything seems to reset something, and after a couple resets I get to an ok state) to get it working without flashes or anything. Other than that, 4k120 seems to work fine.

Using arch linux with nvidia proprietary drivers, RTX 2080 Ti.