HP G2 dock monitors not working with MacBook Pro

俊霏 wrote:

I think my dock is HP – HP Thunderbolt Dock 120W G2 which works fine with windows.

is there any sulotion that can make it works fine with mac os

Based on the symptoms you reported it does not sound like your dock is the Thunderbolt one. That one would look like this

I count five places to plug in monitors: a VGA port (#7), two DisplayPorts (#8), a USB-C port with DisplayPort Alt Mode support (#9), and a Thunderbolt daisy-chaining port (#12). Macs support at most two, and it is likely that this one gets to five by using MST. Macs do not support MST, and the typical symptom is "mirroring" that cannot be shut off.

You would need to experiment to find which combination of outputs worked, but my guess is that the Thunderbolt daisy-chaining port is connected to one signal and that all of the other outputs are connected to another.

https://h30434.www3.hp.com/t5/Notebooks-Archive-Read-Only/Is-the-HP-G2-Thunderbolt-Docking-Station-Compatible-with/td-p/7601256

This is the HP USB-C/A Universal G2 dock that depends on the DisplayLink workaround.

It requires installation of a DisplayLink driver. No driver, no video. If it "works fine with windows" on a Windows PC that has had the DisplayLink driver installed, that says nothing about macOS being to blame when you try to use this dock with a Mac that does not have DisplayLink drivers installed.

HP Support – HP USB-C/A Universal Dock G2

(But if you have a DisplayLink-based dock and there are changes in macOS that break the the drivers needed for the workaround, you will generally have to depend upon your dock vendor, or more likely, Synaptics, to fix them.)

MacBook Pro A2141 looks up to several slightly-different MacBook Pro 16-in 2019. These have as many as four Thunderbolt-3 ports.

In general, Macs do not support multiple displays on one USB-C cable at all. In general, a Thunderbolt cable to a genuine ThunderBolt dock is required to support up to TWO displays on one Thunderbolt cable.

The HP G2 disk is a USB-C dock, and would not support two displays on a Mac in most circumstances. Windows has different standards. On a Mac, a ThunderBolt Dock would be required.

HP suggests this may be a DisplayLink device. if that is correct, with added DisplayLink software, a DisplayLink device can sometime support more displays, with strongly reduced responsiveness. Resolutions must be modest to avoid exceeding the bandwidth of a USB-C connection. DisplayLink displays are NOT suitable for Full-motion Video.

A search for "HP G2 Dock" turns up at least two results:

• HP – HP USB-C/A Universal Dock G2 . While HP claims that "this dock works with both HP and non-HP USB-A-, USB-C™-, and Thunderbolt™-enabled notebooks", it is clearly not a Thunderbolt dock. USB-A is not designed to carry video signals at all, so when you see something like "Use the included USB-A Adapter to connect your USB notebook to the dock and access your accessories and up to two 4K displays," that is a sure sign of the presence of some second-class workaround like DisplayLink. Sure enough, HP says "The dock is driven by DisplayLink."
• HP – HP Thunderbolt Dock 120W G2 . This one is a Thunderbolt dock, but it has at least four places to hook up displays: two DisplayPorts, a VGA port, and a Thunderbolt daisy-chaining port. This strongly suggests that the dock uses DisplayPort MST (which Macs do not support) to drive some of the outputs – and that there are only certain pairs of outputs that will support two monitors running in extended desktop mode on a Mac. (This issue has come up with other similar HP and Dell Thunderbolt docks before.)

There may be others, but I didn't do an exhaustive search. It appears that for HP, "HP G(whatever)" as part of the name of a dock refers to a model line, not necessarily to a single model.

俊霏 wrote:

Yes, my dock is HP Thunderbolt Dock 120W G2, which has two dp, one vga and and a Thunderbolt daisy-chaining port. As you said, mac os not surport it.

HP claims on page 2 of their "HP Thunderbolt Dock G2 – Technical White Paper" that the dock is compatible with macOS.

They also say elsewhere,

"For MacOS, HP does not provide ethernet and audio drivers. Firmware updates on Windows-based host systems only. The following features are not functional on non-HP supported or non-HP notebooks: Power button to turn on or wake the system; Wake on LAN from warm and cold dock; Wake on LAN from S4/S5; MAC Address Pass-Through S0, S3, S4, S5 warm and cold dock."

I would suggest that if you continue to have problems with HP's dock, that you contact HP support and ask them to provide support for a dock that they claim to be compatible with macOS.

俊霏 wrote:

I have a hp g2 dock and mac book pro(A2141), i connect the dock to the mac book, the mouse connetec to the dock work, but two monitory conntected to the dock now work(no signal). Does not this mac book not surport the hp g2 dock?

"No signal" would suggest that you have the "HP USB-C/A Universal Dock G2", or another one like it, that relies on the DisplayLink workaround.

DisplayLink does not take advantage of the first-class, hardware-accelerated video from your MacBook Pro. You need an external "stunt box" with a DisplayLink chip set and a special DisplayLink driver on your computer, to get any output. Either alone is not enough. You must have both the "stunt box" and the driver to get any signal.

Synaptics is the "arms supplier" who provides DisplayLink chip sets and drivers. They make their money selling DisplayLink chip sets to "stunt box" manufacturers, and most or all of those vendors then tell their customers to install drivers from the Synaptics site.

Synaptics – DisplayLink Graphics

With MST, the usual symptom is that you get video on both monitors – but it's the same video on both; and the computer only detects one of the two displays. (The dock is essentially feeding one signal to two monitors.) If your dock was a "HP Thunderbolt Dock 120W G2", you might run into that problem.

Note that the online user guide for the HP USB-C/A Universal Dock G2 tells you to go to the HP Support site to get drivers. If you do go to that site, you will find only Windows drivers there.

I just saw where the user guide says "HDMI can only be used with computers that support DisplayPort alt mode."– so it sounds like HP is driving the HDMI port off of a hardware video signal, and the DisplayPorts off DisplayLink (a different thing despite the similar-sounding names).