2019 16" MacBook Pro External Monitor Issues

This post is to document a handful of issues I’ve experienced with my 2019 MacBook Pro when connecting to external monitors.

  • GPU: AMD Radeon Pro 5500M
  • Monitors: Dell U2718Q 27” 4K (x2)
  • Dock: CalDigit TS3 Plus

GPU Issue

Dell U2718Q

I had this issue happen several times with my previous 2015 15” MBP; keeping this post

For some reason, the monitor will sometimes refuse to be “seen” by the Mac via mini DisplayPort, and will only function over HDMI.

To resolve this issue, you can reset the Dell monitor.

  • Shut down your MacBook Pro completely
  • Disconnect all cables from the monitor and the MacBook
  • Turn on the MBP and log in normally.
  • Press and hold the monitor power button for 10 seconds
  • Reconnect power to monitor
  • Reconnect DisplayPort to mini DisplayPort cable to the monitor first, and then the MacBook Pro.
  • Turn monitor on, and switch source to DisplayPort if needed.

No idea this happens; seems to occur up every 3-6 months. Have not had any issues with my 2019 16” MBP (knock on wood).