The TBT4-UD5 is a Thunderbolt 4 docking station based on the Intel Goshen Ridge chipset. The display output capabilities of the TBT4-UD5 are ultimately determined by the display output capabilities of the host system.

Thunderbolt 4 and Thunderbolt 5 host system:

When the TBT4-UD5 is connected to a computer with a Thunderbolt 4 or Thunderbolt 5 port, the maximum number of displays that can be connected to the docking station is two. 

The TBT4-UD5 has 2 built-in HDMI video output ports, and one downstream Thunderbolt port.

A USB-C cable or video adapter can be connected to the downstream Thunderbolt 4 port to connect a display.

The video outputs via the TBT4-UD5 are provided on a ‘first come, first served’ basis. This means that if a display is connected to the downstream Thunderbolt 4 port on the dock, you can connect one more display to one of the HDMI ports.

If both HDMI ports are occupied, the downstream Thunderbolt 4 port will not be able to output to a display. However it will still function as a Thunderbolt 4 port in other aspects.

What Hosts Will Not Support 2x Displays?

Thunderbolt 3 and USB Type-C host system:

Host systems with only a Thunderbolt 3 or USB Type-C port will be limited to a maximum of one display.

Early Apple Silicon MacBook's:

Base model M1 / M2 MacBook's can only support a single display. Base model M3 MacBook's can support dual displays in clamshell mode only.