View Single Post
Old 01-13-2020, 12:35 PM   #7
rboerner
Super Moderator
 
Join Date: Jan 2015
Posts: 618
Default

Quote:
Originally Posted by HeneryH View Post
Does anyone know the technical reason that Win10 laptops with a Thunderbolt3 output can use this dock to extend two external monitors while OSX can't?

Or secondarily, what is the technical reason OSX CAN display to two in mirror mode but not in extend mode?
My impression based on the specifications of the dock (https://support.lenovo.com/us/en/solutions/acc100348) is that the unit has an internal DisplayPort MST hub inside the unit in order to facilitate the multiple display support (note that 'DisplayPort' is not the same as 'DisplayLink').

DisplayPort MST hubs are not supported in macOS. When such devices are connected to a macOS system, the behavior is that all displays connected to the DisplayPort MST hub will 'mirror' each other, as you describe.

In short, the problem appears to be the internal limitation of macOS.
rboerner is offline   Reply With Quote