Docking through Thunderbolt 4 vs GPU output?

I currently have a Thuderbolt 4 dock to easily swap out my 13" AMD Framework, work MacBook, and Steam deck with a single Thuderbolt 4 cable.

I’m researching how this will work if I upgrade to a 16" Framework with the GPU expansion.

Is the USB-C port on the GPU Module itself a Thunderbolt4 port, capable of docking to not only a monitor but also keyboard/mouse/speaker/webcam/microphone/network/etc?

Alternatively, could the regular Thunderbolt4 ports from the mainboard output video from the dedicated GPU?

Thank you all in advance.

The dedicated GPU will be able to give video to a display connected to the USB4 ports the same way it can display on the built in screen. The port on the GPU is only for DP alt mode and won’t let you connect other things as it is essentially a DisplayPort connector.

The GPU module port is exclusively for display and USB 2.0 data. Docks that require USB4 will not work (Thunderbolt 4 is just a certification for USB4 implementations that meet certain requirements and have passed through a costly certification process).

Somewhat.

The regular ports on the mainboard are physically connected only to the integrated GPU. Modern operating systems can use a technique where the dedicated GPU does most of the work but hands off to the integrated GPU for outputting the display signal. This incurs a performance penalty (typically around 5-10%) compared to being connected to the port on the dGPU.

Don’t forget that those 5-10% losses are those they already experience from using the GPU on the integrated display as it is connected to the iGPU and the dGPU pushes its frames into the VRAM of the iGPU to be displayed which is how getting the frames out through the USB4 ports will work as well.

The Framework Laptop 16 is equipped with a MUX for the main display. A MUX is a device that can switch the physical connection of the integrated display between the iGPU and dGPU.

Afaik the MUX isn’t supported by the Linux drivers, so on Linux (or on Windows with the MUX disabled) the laptop behaves in the way you described.

Oh, then I’m mistaken, I was sure that essentially all laptops that have both iGPU and dGPU and switches to the dGPU under load just pushed it to the frame buffer.

It is the most common option as it is the cheapest but in this case there is a mux.