Limited resolution on 2nd external display

[Wall-EE]

I have 2 external monitors connected via a USB-C dock G5 to my Elitebook 840 G7. Both monitors support 2560x1440 resolution, but for some reason I can't select this resolution on both at the same time, one of them is always limited to 1280x800 max. Is this a limitation of the laptop or the docking station?

[banhien]

@Wall-EE 

Please check the following table

   

I tested 3 displays before

Regards.

[Wall-EE]

Thankyou Banhien for this useful table. I guess I am in the case "Dual 2.5K displays", which should work with all DP versions in high res mode?

Apparently it is not the dock that is limiting, so it must be the laptop. I confirmed this by borrowing a G8 laptop and I get 2.5K on both displays via the same dock.

One of the displays supports USB-C so I tried connecting it directly to the spare USB-C port on my G7 laptop. In this configuration, both displays work fine at 2.5K .

To summarise the configuration which works:

Display 1 (2.5K):  connected via DP or HDMI to dock which is connected to laptop USB-C port 1

Display 2 (2.5K): connected directly to laptop USB-C port 2

I conclude that the G7 laptop can only support one 2.5K screen per USB-C port.

Regards.