Hardware:

* Laptop: Lenovo Legion (Intel Raptor Lake + NVIDIA RTX 4070 Laptop GPU)
* Dock: Lenovo ThinkPad Thunderbolt 5 Smart Dock 7500 (40BA)
* Dock firmware: Latest available via fwupd
* OS: Arch Linux
* Kernel: 7.0.12-arch1-1
* Thunderbolt: Authorized and functioning normally

Problem:

Displays connected to the dock's integrated DisplayPort or HDMI outputs fail to establish a usable display connection under Linux.

Displays connected to the dock's Thunderbolt downstream ports using USB-C to DisplayPort adapters work correctly.

Observed behavior:

* Thunderbolt dock is detected and authorized successfully.
* USB, Ethernet, and audio functions of the dock work normally.
* External displays connected to Thunderbolt downstream ports function normally.
* Displays connected to the dock's built-in DisplayPort or HDMI outputs briefly wake up, display "Searching for signal", then report "No Signal".
* Linux briefly creates MST connectors (observed as DP-7, DP-9) which subsequently disappear.
* NVIDIA logs repeatedly report:

  nvidia-modeset: WARNING: GPU:0: Unable to read EDID for display device DP-2

Troubleshooting performed:

* Fresh Arch Linux installation
* Latest available kernel
* Latest dock firmware via fwupd
* Thunderbolt authorization verified via boltctl
* Tested with Intel i915 graphics path
* Tested Hybrid Graphics mode
* Tested Discrete Graphics mode
* Forced EDID override via drm.edid_firmware
* Forced display modes via video=
* Disabled DSC via i915.enable_dsc=0
* Multiple monitors and cables tested
* Direct laptop HDMI output works correctly
* Thunderbolt downstream video outputs work correctly

Expected behavior:

Displays connected to the dock's integrated DisplayPort and HDMI outputs should function normally, the same way they do when connected through the dock's Thunderbolt downstream ports.

Additional observations:

The issue appears isolated to the dock's integrated display hub path (USB device 17ef:3116, identified as Lenovo VMM9322). Thunderbolt transport itself appears functional, as downstream USB-C display outputs operate correctly.