Hooking up monitors to use with both laptop and desktop

Hey there, I have this dock for a while now but trying out a different set up.

Currently I have three displays: laptop, HP monitor through DVI input, and LG monitor through HDMI 2K (I tried hooking up both of the external monitors through HDMI but whichever one was plugged in to the 4K port didn’t work, confirmed by swapping the cables between the two HDMI ports).

What I would like to do is have this hooked up so that I can use the two external monitors if I wanted to just use my desktop computer. Currently if I power up the desktop computer both the monitors are black but something is working because I can see the mouse cursor move when I move it. But nothing else happens.

Hi Christopher,

Thanks for posting!

I assume you are connecting the UD-ULTCDL dock to your desktop via a USB-A to USB-C adapter. Firstly, you’ll want to make sure that the two monitors are connected to the DVI port and the HDMI 2K ports on the dock. These two ports are powered through DisplayLink graphics, which will just require that the DisplayLink driver is installed onto your system.

The HDMI 4K port is powered through USB-C Alternate Mode (Alt Mode) graphics, and it requires that the USB-C port on the host supports Alt Mode video (not all do). I suspect that the USB-C port on your laptop may not support Alternate Mode video, and we can explore this further if you would like.

Based on the issue so far, the first steps we’ll want to take is to make sure that the software used by the dock is in a good state by reinstalling the DisplayLink software and running the DisplayLink cleaner tool on your desktop computer. To do so, please follow these steps:

  1. Disconnect the dock from the system and please remove the power cable from the dock so it turns off completely (this is important so the unit resets). Please keep it disconnected until the last step
  2. Uninstall any and all software with ‘DisplayLink’ in the title that is present from within the Control Panel → Programs and Features. Don’t worry if these entries are not present or if the process does not work, just move onto the next step
  3. Download, extract and run the DisplayLink cleaner tool (https://s3.amazonaws.com/plugable/bin/DisplayLink/DisplayLink+Installation+Cleaner+9.1.1462.exe)
  4. Once the Cleaner has been run, reboot (even if not prompted to)
  5. Now download and install the 9.0 M1 DisplayLink software (https://s3.amazonaws.com/plugable/bin/DisplayLink/DisplayLink+USB+Graphics+Software+for+Windows+9.0+M1.exe)
  6. Reattach the power cable to the dock first. Once the dock is powered on, reconnect it to your system which will trigger the final portion of the installation

Please let me know if this helps at all and we can take the next steps from there.

Thanks for giving us a chance to help!


Thanks for the suggestion.

I went through these steps. So right now I have my desktop connected to the dock. If I have both monitors connected through the dock, what I see is my Windows background on both monitors. I can see my mouse cursor move. If I try to open a window or something it looks like it is opening a window but I can’t see it on either of the two monitors. I can see in the task bar I have a folder open or Chrome open, but I can’t “open” it on either of the two monitors. Its almost as if it is trying to display on a different display that is even hooked up.

I did unplug the HDMI from the dock and went straight to my computer so at least I could open this window to type a response. I still have the second monitor connected to the dock via the DVI port. Interestingly enough, when I do this (HDMI to PC and DVI to dock) I can use both of the monitors exactly how I would like to be able to use it.

Just to test, I disconnected the desktop from the dock and connected my laptop. I have display on my laptop and on my one other monitor. The larger monitor doesn’t display because that’s connected to desktop via HDMI. But if I connect that HDMI back to the dock, I again have my laptop and two external monitors displaying what I expect from the laptop.

If this makes any difference, when I have both of my monitors connected to the dock, and my desktop computer connected to the dock, on what I assume is monitor 2, I can scroll my mouse over to the right and it enters monitor 3, if I go left it goes back to monitor 2 and if I continue going left it scrolls OFF monitor 2 to what I would assume is monitor 1, except there is no monitor 1 in this case.

Thanks for getting back to me.

It sounds like we’re dealing with a "phantom display’ issue, where the host mistakenly believes that a display is connected when there isn’t one. This results in the problems you describe, where you’re able to drag your mouse over to an unknown monitor, and applications are opening but not visible on any monitors.

When you navigate to your Windows Display settings, do you see this additional “phantom display”? We can check this and workaround around the issue by following these steps:

  1. Right-click on your Desktop, then choose Display settings
  2. Under Rearrange your displays, please observe the numbered monitors and see if you can locate the "phantom display’. You can click on the Identify button to help you match up which monitor corresponds to which number
  3. If you can locate the “phantom display”, click on the monitor, then scroll down to the Multiple displays dropdown field, then select Disconnect this display

Please let me know if this helps, or if you do not see these settings.


Well, that was it! I don’t know how that happened but that fixed it. There was a “display 1” hooked up somehow, I disconnected that, so now I have display 2 and display 3 connected, and display 1 is just there. I’m not sure how to get rid of it, or if I even can or should, but otherwise this is all working as I expected. To test, I switched from the desktop to the laptop and had all three displays working, switched back to the desktop and had just the two displays working.

Thanks for your assistance.

Glad to hear that this helped work around the issue!

I’ll be closing this thread, but should you have any future questions or concerns, please do not hesitate to open a new post or reach out to us directly at support@plugable.com. We’re glad to help.