Pop!_OS AMD 7040 with 2x dell u2725qe (MST, DSC, daisy chain)

Framework Laptop 13 Linux
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I was able to get dual 4k-30bit-60hz thunderbolt 4 monitors (dell u2725qe) working reliably with my 7040 FW 13 (connected via single rear USBC port).

I was having some issues where the second monitor in the chain wouldn’t reliably come back from monitor sleep.

What I think fixed it was disabling MST on the second monitor in the chain. IDK if the second monitor was waiting for a nonexistent 3rd monitor in the chain to wake or something (no idea how MST works) but in any case, it seems to fix it for me.

Other things I changed, maybe would help you:

  • FW → 1st monitor = USBC cable. 1st monitor → 2nd monitor = DisplayPort cable
  • Turned on gaming mode in BIOS (more RAM for GPU). No idea if this did anything though.
  • Upgraded to latest firmware on both monitors (M2T102) and framework laptop
  • Oh, and in order to get wake working at all with a USB keyboard/mouse, I had to enable USB wake for all devices. LLM/google can help with this, nothing special here. USB wake must be enabled for the embedded monitor dock, that’s where the wake signal comes from btw

I’m running PopOS 24 beta, but the problem also occurred in 22.

Anyways thought I’d post if anyone else had issues.

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Update: I was able to get to 120hz on both monitors with a higher quality usb4 cable (1.8m length).

I never would have guessed that the USB4 cable that comes with the Dell monitors is low quality!

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Thank you! I have the same setup and was initially disappointed to not even get one monitor (the u2725qe) on the thunderbolt port, leaving me with usb data + hdmi/dp + power charger.

I will look forward to making it work with two monitors like you did on one cable!

note: I am using linux.