Thank you for contacting Plugable support! Sorry to hear about this issue. I’d be more than happy to assist you.
Neither of these systems support USB-C VESA DisplayPort Alternate Mode video output. This is required for the HDMI port on our dock to function. We mention this important detail on our Amazon and Plugable.com website.
Systems without USB-C Alt Mode capabilities are limited to just two displays. Unfortunately this feature cannot be added to either of your computers, only systems that ship from the factory with Alt Mode support can take advantage of the 4K HDMI output on our dock.
Please don’t hesitate to let us know of other questions.
Thanks again for contacting Plugable support and best wishes!
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