USB-C dock with USB-C DP alt mode video output?

Hi I recently switched from Intel based HP ZBook 14u to AMD based ThinkPad P14s Gen2 laptop. I thought that my Thunderbolt 3 HP docking station will just work and downgrade to USB-C connection but it seems to not be the case. So I picked up Thinpad Pro Docking station however my usb-c monitor doesn’t work when I’m connecting it to usb-c port in this docking station. I’m using ASUS usb-c only portable monitor.

My setup goes as follows:

Laptop —[usb-c]–> dock —[usb-c]–> monitor

it used to work when I was connecting TB3 Dock to HP and then display to TB3 passthrough port. I’d like to achieve similar result with this AMD ThinkPad P14s Gen2. It works when I connect monitor directly to usb-c port in laptop but I’d like to connect it do docking station since having to connect two cables every time is kind of PITA.

I considered getting DP → USB-C bidirectional cable but the problem is that this monitor is also powered by USB-C power delivery and I couldn’t find any DP → USB-C cable with external power injection.

Only the 2nd generation of TB3 controllers (“titan ridge”) can handle non-thunderbolt inputs. Also, most TB3 docks expose 1 DP connection to an MST-Hub and further Display outputs and the 2nd DP connection is made available through the TB Out.

With DP Alt Mode only, there is only 1 DP connection and the dock may be hardwired to only use this single connection on the MST-Hub side, where it can still be split up into multiple ports. The TB Out is then commonly limited to a pure USB 2.0 port.

Such docks as the Dell WD19TB have a non-TB USB-C (DP capable) port that still works in back compatibility mode (although not 15W if you need that) and the modern TB4 Docks/Hubs that have multiple TB-Outs can route a DP Alt Mode to any of their outputs.

But if your source-devices do not have TB anymore, why buy a new TB dock anyway.

I’m not looking for TB dock. I’m looking for some kind of dock that will allow me to connect my usb-c monitor with DP Alt Mode + PD on single cable. I don’t care if it’s TB or not, laptop doesn’t have it anyways. It’s just that USB-C dock that I tested so far doesn’t work with usb-c monitor connected to its usb-c output. Precisely this dock that I tested:

Does not support usb-c display. This one doesn’t either:

Tested both. I’m looking for something that will work with my monitor. It’s this type of monitor:

power + display on one usb-c cable.

Ok then.
Does your monitor work with 7.5W or does it need the full 15W you are likely to only get from TB-Ports?

As I mentioned, Dell’s WD19 line has such outputs (TB and non-TB).
The HP Thunderbolt Dock G2 should also have such a port.
And Thunderbolt 4 Hubs such as the Caldigit Element Hub, the Anker Thunderbolt 4 Hub, Kensington SD5700 have actual Thunderbolt Ports with 15W that also work for your purposes on non-TB hosts.

It works when I’m connecting it directly to laptop which doesn’t have TB so there’s possibility it works with 7.5W.

I’ll check out HP Thunderbolt Dock G2 since we have some of those in office.

I connected HP Thunderbolt Dock G2 and indeed it downgraded to usb-c and peripherals worked, however USB-C monitor did not. It has own battery so it wasn’t power issue, just laptop did not detect it as DP alt mode display using this dock. Monitor behaved as if it was connected to USB-C charger (started charging battery but did not detect any signal and it was not visible in OS as available display). I tried both front and rear usb-c port in dock.

I would expect only the left one, the one with explicit mention of displayport support, to work in back-compat mode. The Thunderbolt-Output is likely only a pure USB 2.0 output when not attached to a Thunderbolt Host.

This would be identical to the Dell WD19TB Dockingstations, that I own.

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oh I didn’t notice there are two usb-c ports on the back. I’ll try that one as well then

I checked usb-c port you mentioned and it does indeed work. I didn’t see it before due to placement of dock on colleague’s desk. So I guess it’s acceptable solution, thanks.

But I guess I’ll get Dell docking station you mentioned then since I really don’t like this HP dock form factor.