Dock Compatibility: Plugable TBT4-UD5 (Thunderbolt 4)

Framework Laptop 16 Linux
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Plugable TBT4-UD5 Dock

Working:

  • USB-C PD
  • USB-A downstream ports
  • USB-C downstream ports
  • RTL8153 USB Ethernet (2.5GbaseT)
  • HDMI port 1 (only when connected to port 2 on FW16; does not work properly when connected to port 1 on FW16)

Tested with:

  • Debian Testing (kernel 6.7.12-1, amdgpu firmware 20240410, KDE Plasma 5)
  • Ubuntu 24.04 (kernel and firmware as provided in installer, KDE Plasma 5)
  • LG 34UC88-B display
  • LG 27UK500 display

HDMI behavior when connected to FW16 port 1 (USB4/TB4) is quite strange (and both displays work fine when connected directly to FW16 using an HDMI expansion card) - sometimes the display will be detected, but with only 640x480 resolution available; other times the laptop locks up and has to be power cycled when the display is attached to the dock. The display works fine when connected to FW16 port 2 (USB3.2).

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If you can reproduce using the latest kernel (6.9-rc7) please post a bug to Issues · drm / amd · GitLab with logs and more details.

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Just updated the post: I’m not sure why I didn’t test this before, but the display works fine when connected to port 2 on the FW16.

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I just got the TBT4-UD5 and have the same problem with an LG34" display. So glad I found this, I had the USB-C module in port 1, switched to 2 and it works fine now. I’m using Fedora 40, but don’t have the latest kernel RC installed though. Thanks for posting this!

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I’m having dock issues as well.
I have the discrete GPU module and when connected to a TB4 dock with two Display port monitors connected to the dock the computer only sees one of them. Oddly, if I restart it randomly chooses which monitor to use so I know the dock isn’t an issue.

I tried two different docks. One is the HP USB C G5 essentials dock and the other is the Razer TB4 dock.

With this said, if I connect to a USB C module in Port 4 both displays are able to be used along with the built in display.

So long story short I fixed it by not connecting directly to the USB C on the Graphics module but it still bothers me that I can’t figure out why connecting there doesn’t allow for more than one monitor and the built in display.

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I’ve got the Debian 6.9.7 kernel installed now and the behavior hasn’t changed; port 1 still produces a 640x480 display with no options to change it.

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Thanks for this discussion. I was also having this problem with external monitor resolution until switching my USB-C module to port 2 which is very strange since only ports 1 and 4 are the only ones listed as supporting USB4. Could this be a USB driver issue? I guess it’s not such a big deal now that there is a work around but very curious as to what the cause might be!

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using a surface laptop 5 with the TBT4-UD5, I can only get one of two external monitors to function. Both monitors have been tested and work fine independently. The USC port to monitor works fine. The HDMI to USB-c does not - it cycles constantly - it recognizes the monitor then drops then recognizes it, etc.
Any suggestions

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I doubt you’ll get much assistance here as this forum is dedicated to Framework products.