RE: Dell XPS15 9560 with Dell TB16 dock. Dell 4K external monitor via miniDP to DP constantly disconnects.
Thank you for your message.
Have you tried to reseat the mDP cable or try another cable to check if the issue persists?
Do you have any issues with the other posts like Ethernet & USB?
When the monitor disconnects, do you get a self-test message on the screen?
For my reference, please click on my Dell username & send a private message with the service tag, registered name & email address.
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