On a Laptop 16 equipped with an AMD Ryzen 9 7940HS processor and running Zorin OS 18 (Ubuntu/Debian-based), I encountered significant difficulties getting my Dell WD19TBS Thunderbolt dock to work.
Kernel 6.14.0-35-generic
It was recognized only sporadically. I spent my time unplugging/replugging, power-cycling the dock, and rebooting the laptop.
Even when it was listed by boltctl list (which happened randomly), it was shown as “not connected.”
All USB peripherals connected to the monitors—which were themselves plugged into the dock—worked fine (mouse and keyboard via dongle, external webcam, soundbar, etc.).
However, the monitors connected via Mini DP were hit-or-miss. And even when they did manage to work, the behavior when waking from sleep was even more unpredictable.
Searching through the forums yielded no results.
After extensive investigation, I believe I have found the cause. I started, of course, by updating the dock’s firmware using fwupdmgr. But most importantly, what changed everything was a specific BIOS setting.
“USB4 device measured boot” is enabled by default. I disabled it, and since then, I haven’t had a single issue. The dock is stable and operating at full capacity.
boltctl info c9030000-0072-740e-830f-72c764f47106
● Dell WD19TB Thunderbolt Dock
├─ type: peripheral
├─ name: WD19TB Thunderbolt Dock
├─ vendor: Dell
├─ uuid: c9030000-0072-740e-830f-72c764f47106
├─ dbus path: /org/freedesktop/bolt/devices/c9030000_0072_740e_830f_72c764f47106
├─ generation: Thunderbolt 3
├─ status: authorized
│ ├─ domain: dadd3804-a0f6-4f56-ffff-ffffffffffff
│ ├─ parent: dadd3804-a0f6-4f56-ffff-ffffffffffff
│ ├─ syspath: /sys/devices/pci0000:00/0000:00:08.3/0000:c3:00.5/domain0/0-0/0-2
│ ├─ rx speed: 40 Gb/s = 2 lanes * 20 Gb/s
│ ├─ tx speed: 40 Gb/s = 2 lanes * 20 Gb/s
│ └─ authflags: none
├─ authorized: dim. 04 janv. 2026 11:34:22
├─ connected: dim. 04 janv. 2026 11:34:19
└─ stored: sam. 27 déc. 2025 11:10:30
├─ policy: iommu
└─ key: no