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macrumors newbie
Original poster
Mar 11, 2010
Sausalito, CA
I am trying to use this older Apple Cinema Display (Mini DisplayPort) as a second monitor with my LG UltraFine (thunderbolt 3) display. I am running the Cinema Display through an OWC USB-C Dock which both has a Mini DisplayPort and also supplies power to the MacBook. Both work independently with my 2019 16" MacBook Pro (maxed out specs). When I plug both into the MacBook, only the LG UltraFine display works.

Is there any way to use these two displays at the same time?

LG UltraFine 5K (27MD5KA-B): 27MD5KA-B
Apple Cinema Display:


Jakob Dam Jensen

macrumors newbie
Jul 17, 2020
Aarhus, Midtjylland, Denmark
Hi. I had the same experience with my Dell display when used with my LG 5K. I found out that I had to have them connected on each side of the laptop. Have you tried that? I don‘t think you can have a 5K display and another display plugged in on the same side of the Macbook Pro.
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