Two Displays Show as one via TB4 Dock

HP – HP Thunderbolt 4 Ultra 180W G6 Dock

"1 Thunderbolt™ 4 with USB Type-C® 40Gbps signaling rate; 1 USB Type-C® 10Gbps signaling rate (USB Power Delivery, DisplayPort™ 1.4); 2 USB Type-A 5Gbps signaling rate (charging); 1 HDMI 2.1; 2 DisplayPort™ 1.4; 1 RJ-45 (2.5 GbE)"

I'm guessing that you need to connect one display to the Thunderbolt daisy-chaining port (possibly with the aid of a USB-C to whatever adapter), and the other display to one of the other video ports.

A logical 1st step might be to see if the monitors perform as-desired when plugged in directly to two of your MBP’s TB ports w/ a pair of high-quality TB cables

If so, move forward step-by-step to your final desired configuration.

Servant of Cats wrote:

The four video ports to the left (USB-C (DP), DP1, DP2, HDMI) may all run off the same signal when connected to Macs. I'm pretty sure that the two dedicated DisplayPorts do.

If the dock uses MST, which is certainly possible, then that makes sense. That’s why I use and recommend Mac-friendly docks, something HP is certainly not known for.

That dock has more than two places where you can plug in displays. Thar means that it probably drives some of its outputs in ways the Mac does not support (I.e., using DisplsyPort MST). There may be only certain combinations of two outputs that actually are getting separate video signals from the Mac.

I would suggest trying to see if you can get two displays to work with this dock, by trying a different combination of ports. Specifically, I’m guessing that you want to hook one to the Thunderbolt daisy-chaining port, using a USB-C adapter if necessary.

the "JCD542 USB-C Dual Display docking station" works because it uses the J5 create software indistinguishable from DisplayLink software. It is NOT a full speed, full refresh rate connection when used with a USB-C input.

DisplayLink technology creates a "fake" display buffer in RAM, sends the data out over a slower interface to a stunt box with DisplayLink custom chips that put that data back onto a "legacy" interface. It is not a true "accelerated" display, and it can suffer from lagging. Just adding the DisplayLink Driver is not adequate to get a picture -- you need a DisplayLink "stunt-box" or a Dock that includes DisplayLink chips.

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It may be acceptable for a second display showing slow-to-change data such as computer program listings, stock quotes, or spreadsheets, but NOT for full motion Video, not for Video editing, and absolutely not for gaming. Mouse-tracking on that display can lag, and can make you feel queasy.

In a pinch, it may even play Internet videos (as one user put it) “without too many dropped frames".

If you are only doing program listings spreadsheets, stock quotes, and other slow to change data, DisplayLink can work for you, but requires you to make some strong compromises.

"I've got a Macbook Pro 14inch with the M4 chip, plugging into an HP G6 Thunderbolt 4 dock, and with two monitors plugged into that via display port. When I plug the dock into the MBP, it displays a mirrored image on my two external monitors, and when I look in system settings - it only shows as a single display. I'd really like these to be extended to show different content on both. How do I go about fixing this?"

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Using a Dual Display Docking Station:

Use this Docking Station: JCD542 USB-C Dual HDMI Docking Station - j5create

When Connected, try Mirroring the Screen with the Keyboard:

• No Touch Bar: [Hold Down: command + Press: F1]
• With a Touch Bar: [Hold Down: command + Press: dim display on the Touch Bar]

Brydge (Stone Pro), OWC, Sonnet, CalDigit.