Reliability of Docking Snapdragon X PC’s with Multiple Monitors using DP MST

Curious if anyone has seen issues reliably docking Snapdragon X PCs with multiple monitors using DP MST. I have seen issues with two Surface Laptop 7 PCs and I’m wondering if this is a general issue with the Snapdragon-based hardware or something with the Surface line.

I have a Dell Ultrasharp (U2723QE) with built in USB-C dock that provides DP MST. I connect the Ultrasharp to the Surface Laptop using USB-C/TB4 cable. I chain a smaller Dell P1917S to the Ultrasharp using a DP cable. This gives me three monitors. I regularly see issues where I get no video on one or both external monitors when docked. Often the P1917S is not detected at all. This even occurs when the machine simply wakes the display but has otherwise been docked for a while. Sometimes this can be resolved by powering the primary monitor off and back on. Sometimes disconnecting and reconnecting the USB-C/TB4 cable from the PC will resolve. Sometimes, it takes a reboot of the laptop to resolve. It’s been frustrating and I’ve been unable to find a reliable solution.

I’ve tried multiple USB-C/TB4 cables. I updated the monitor firmware to latest. I installed the latest Dell monitor “drivers” on the PC. Made sure Windows had all updates applied and there were no hardware issues. I’m out of ideas.

I have an older Surface Laptop Studio (1st gen) that I’ve used for three years and has never exhibited this problem. I have a new work HP laptop that does not have this problem. It seems specific to the Snapdragon hardware.

I was excited about the possibility of an ARM-based laptop with great battery life. Took advantage of the end of year sales and got two machines–one for myself and one for my wife (she was long overdue with a 1st gen Surface Laptop). I got the top end specs for development, and she got a more standard consumer configuration (both Snapdragon X Elite). Both exhibit this problem. We love the machines and the battery life. I really wanted to love the new Snapdragon X-based machines based on all the hype (which it has absolutely lived up to). I do love it, but the docking issue is annoying.

Docking with two external monitors using DP MST is probably an edge case, but I regularly use it. I could use two cables to connect the monitors. It wouldn’t be the end of the world. I want the clean, simple single cable connection I’ve paid to get (with monitors and laptop). I’m prepared to send the machine back to Microsoft and try again in a year to see if things have improved. It’s hard to swallow paying for the top of the line and face this issue. Hoping someone has an idea.