Multiple Monitors on HP Zbook 15u G6

[PaulHy]

I have a HP Zbook 15u G6 and I am attempting to add (3) external monitors, for a total of (4) displays.

Unfortunately the documentation from HP was inconclusive about how many external monitors could be connected.

I have the HP ThunderBolt 120W G2 dock connected and via USB-C to the laptop.

On the dock there are (2) DPs, (1) VGA, (1) USB-C for DP, (1) USB-C for another Thunderbolt connection.

On the laptop itself there is a HDMI port.,

I have tried multiple configurations with the (3) monitors connected via DP or HDMI to the dock as well as through a USB-C to HDMI (F) connector, but I can only get (2) monitors working at a time with the laptop display.

Is there a way the (3) should be connected that will allow for each of them to function as an extended display along with the laptop display?

[banhien]

@PaulHy 

Depending on resolution of your monitors, please check a table of the following document

            https://www8.hp.com/h20195/v2/getpdf.aspx/c04168358

Regards.

[PaulHy]

Thank you very much for this link and document.

However, I think my host laptop is not allowing the number of displays.

If you look at this document https://h20195.www2.hp.com/V2/GetPDF.aspx/4AA5-2657ENW there is an entry for HP ZBook 15u G6 that shows in the table that Up to 3 displays are supported with a dock. What it doesn't say is whether that is 3 displays with the dock is in addition to the laptop display. So that may be my limitation.

In Windows Display Settings it will show all 4 displays, but one will be grayed out. I can then indicate to extend to this display, so that particular display will activate, but then another one of the 4 will get grayed out, leaving me with only 3 total.

So I am discouraged, as I purchased this dock to be able to get to 4 total displays, and it doesn't look like that will happen.

Is there a BIOS setting that is blocking this? 

Should I place a support call with HP regarding the laptop?

Any suggestions?