MacBook Pro, WD19TBS, two U2520D

Question

Hello,

The setup that I have:

- 2 x Dell U2520D monitors

- 1 x Dell WD19TBS docking station

- 1 x Dell XPS 17 9710 (My personal laptop)

- 1 x MacBook Pro (2019) with BigSur OS (AMD Radeon Pro 5300 graphics and an intel integrated graphics) (work laptop)

When trying to use the Dell XPS with dual display setup in extended mode at maximum resolution supported by the monitors (2560 x 1440) it is just plug and play.

The issue that I have is when trying to have the same setup with the MacBook Pro. I have tried it and retried it. The only thing that I got in extended view is with only one monitor at max resolution and the second one with lower resolution. I tried daisy chaining with DP on the monitors and it doesn`t seem to work or probably I`m not setting them up correctly.

Question: Is there a way to set up the monitor along with the docking station to have maximum resolution in extended mode for the MacBook Pro?

Thank you

PS: Thanks DELL for the ease of setup in between your products.

jphughan · Answer

@gizet  macOS does not support DisplayPort daisy chaining, so that setup isn’t going to work. And in fact that limitation and the way the WD19TBS allocates the two interfaces of video bandwidth received from the system across its outputs combine to create some restrictions on how dual displays have to be cabled to the WD19TBS to operate with Macs. Dell has an article about this here. Is that how you’ve got your displays connected?

gizet · Answer

Hello, jphughan

Yeah, so actually I connected them as in Figure 1. Dual Monitor Setup-1 with WD19TB/WD19TBS dock connected to an Apple USB-C Host. But this has some constrains limiting one of the monitor (the one connected to UsbTypeC/Thunderbolt3) to a lower resolution than the one.

Not sure if I could setup as in the Figure 2. Daisy chaining with thunderbolt. (since my monitors have only one port of usb type-c/thunderbolt per monitor).

jphughan · Answer

@gizet  Thunderbolt daisy chaining requires actual Thunderbolt displays, not USB-C displays.  USB-C and Thunderbolt are not interchangeable terms, and the U2520D does not support Thunderbolt.  I'm not sure why you're having resolution issues given that both the dock and MacBook should be capable of running dual 4K 60 Hz displays in that configuration.  Have you confirmed that the dock is running the latest firmware?  You'd have to perform the firmware update from your XPS.

gizet · Answer

@jphughan Just got the chance to check the firmware of the dock and it seems fine.

gizet · Answer

This is the setup with the dock and how the mac recognize the monitors.

jphughan · Answer

@gizet  I'm not sure what's going on there.  That USB-C/TB3 output is supposed to support up to a 4K 60 Hz display when paired with a Mac or a PC that supports DisplayPort HBR2.  And even with HBR3, where the dock allocates video bandwidth differently, it should still support up to 2560x1440.  I really don't know what's going on in your case, unfortunately.  Sorry!

gizet · Answer

@jphughan Thanks for the help. I'll come back if I find the fix for this problem

Monitors

MacBook Pro, WD19TBS, two U2520D

Was this post helpful?