Only one monitor is detected. Windows 11

I’m setting up my new workstation and my new UD-3900PDZ is only detecting one of two monitors. I have double checked the driver and it is up to date. Please advise.


Thank you for contacting us, I am sorry this is not working as expected and I am happy to help!

This docking station relies on two technologies to support up to three external displays:

  1. The HDMI 1 output port is controlled directly from the computer’s internal graphics controller via USB-C DisplayPort Alternate Mode, an optional USB-C port feature. This also requires connecting the docking station to the compatible USB-C port with the USB-C cable provided with the docking station. USB-A to USB-C cables, adapters, as well as hubs or other USB devices between the docking station and computer will block this video signal
  2. The HDMI 2 and HDMI 3 output ports are controlled by the DisplayLink drivers (Windows) or DisplayLink Manger App (macOS). This emulates graphics hardware in software extending the computer beyond the manufacturer’s design, allowing for the system to support additional displays. This requires that the operating system, the hardware graphics drivers, and the DisplayLink software all be updated to the same or similar levels. I normally recommend updating everything to the latest drivers for the best performance and compatibility, however this may require manually installing some driver updates.

I recommend we start by getting some additional details from the computer to ensure this system supports USB-C DisplayPort Alternate Mode, and I can also check to see if there are likely to be any pending driver updates for the graphics controller based on the versions provided from Windows Update and the manufacturer’s website.
For Windows:

  1. Open the Start Menu and search for “msinfo32” and launch the first search result
  2. Please let me know the values from the following entries ( on the right column ):
    2a) “System Model”
    2b) “System SKU”
  3. Please feel free to attach a screenshot of this window to your reply email if you prefer by using the Windows Snipping Tool ( from the Start Menu search for “Snipping” ) and I can get the details from there

For macOS:

  1. Open the Apple Menu > About this mac…
  2. Please let know the system model details and macOS version from this page
  3. Please feel free to attach a screenshot of this window to your reply email if you prefer by using the macOS screenshot hotkey combination [Command ⌘]+[Shift ⇧]+[4] then dragging a selection box around the window, the screenshot will be saved to the desktop and can then be attached to your reply email.

I look forward to your rely and we can proceed from here.

Thank you,

Plugable Technology

This topic was automatically closed 20 days after the last reply. New replies are no longer allowed.