HP Elitebook 840 G6 and HP USB-C Dock G5 - Does this not support dual 4k60 ??

[INeedHelpPlzzz]

I am using HP EliteBook 840 G6 and HP USB-C dock G5.

In a previous HP support post (https://h30434.www3.hp.com/t5/Notebook-Video-Display-and-Touch/Elitebook-830-G5-with-HP-USB-C-Dock-G...), there unfortunately was not a solution...

As in that post, only one of my 4k monitors (which supports and is connected over DP 1.4 ) is at 3840 x 2160 , but it is limited to 30Hz refresh rate... The other automatically connects as a 1440 x 576 resolution limited at 25Hz refresh rate.

Why is this not working? Is the dock the problem? If so, please recommend a dock compatible with my machine that will support dual 4k60 using either DP 1.4 or HDMI 2.0. 

[banhien]

@INeedHelpPlzzz 

I've got 5 monitors at home, unfortunately none of them is a 4K monitor therefore I can't setup and test. They are old, at least 5 years old but no point for me to buy new monitor(s) now. I will buy one by one when they break.

My suggestion

  (a) Update BIOS of tour machine

  (b) Update firmware of the dock using

            https://support.hp.com/au-en/drivers/selfservice/hp-usb-c-dock-g5/27767205

Some members say they can get two 4K monitors after update BIOS but their machines are not 840 G6.

Regards.

[INeedHelpPlzzz]

Banhien, I will contact our IT dept on Monday and see about this. Thanks for the suggestion.

It's just frustrating to read technical specs sheets that say dual 4k at 60 is supported over the DP1.4's (as well as an additional 4k at 30 using hdmi 2.0) but it actually seems to not be supported... I will update this in the upcoming days.

[TryToDoMybest]

Hello with 840 G7 and USB-C DOck G5 :

but it should be the same for 840  G6

enter BIOS setup, pressing F10 during boot,

than search for "Enable High Resolution mode when connected to USB-C DP alt mode dock", enable this setting.

save configuration.

it it's possbile to have two external monitors at 3840x2160 at only 30 Hz , with notebook lid closed or only one 4K 60 HZ.

I dont remember if you can connect a second 4K 60HZ monitor through the second TB3 port. I can try tomorrow if you still need.

I have 840 G6, USB-C Dock G5 , two 4K monitors , an adpater from USB-C-to HDMI 2.0. SO I can try for you.

For sure a solution able to support  2 monitors at 3840x2160 at 60 Hz , you need aN HP thunderbolt Dock G2 or an HP Universal Dock G2.

bye