@linkref  That is the result of how the D6000 works.  See my post marked as the answer in this thread.  Since your Elitebook 840 G5 has a USB-C port that is capable of both regular video output (DisplayPort Alt Mode) and even Thunderbolt 3, you should consider getting a USB-C or Thunderbolt 3 dock that rely on those native GPU outputs rather then the DisplayLink technology used by the D6000.

Hi,

So the issue is "normal" to your point of view ?

I tried with thunderbolt 3 but the integrated gpu is so weak that i can't handle youtube video without the windows UI going laggy.

The reason why I wanted a displaylink take care of all the render of the monitors and so discharge the native GPU that work.

@linkref  I'm not sure I would call it "normal", since that implies everything is fine.  But I would say that this is an inherent drawback of DisplayLink-based docks, and the fact that you're trying to watch video on high resolution displays makes you more likely to experience that inherent drawback.  Thunderbolt 3 don't make a difference here since the dock it just a regular USB peripheral.  If you were hoping that DisplayLink would free up the Intel GPU, that is not how it works.  DisplayLink still uses the Intel GPU to do the rendering, and then it ALSO has to use the CPU and Intel GPU to compress the rendered video and convert it to regular USB data.  So DisplayLink causes the Intel GPU to do even MORE work, not less, and therefore you are MORE likely to see lag when watching video, not less.

If you're using 4K displays, try getting a Thunderbolt dock like the WD19TBS, or maybe an HP Thunderbolt dock since you have an HP system.  A Thunderbolt dock will be able to run dual 4K displays, and since it will use the native GPU output without having to perform compression and conversion to USB data, you might find that the lag goes away, and you will also avoid compression artifacts if you've noticed those.  If you still notice lag even at that point, then the system's GPU simply isn't capable of performing the way you need it to, in which case you'll need a different system.  Using DisplayLink will not avoid that problem.  But the Intel 620 GPU in that system should be capable of playing YouTube on a 4K display when not having to use DisplayLink.

Ok I think you are right. Because when i use this dock with m1 macbook which as great CPU power, i see no lag there.

I will eventually try e-gpu and leave my feedback here by the end of the week.

@Anonymous  A slow Internet connection would cause video to stutter and buffer, or perhaps degrade in quality if the source supports dynamic bitrate, but it would not cause the video to lag.  The behavior described here is a pretty widely observed issue that occurs when using displays that are driven by DisplayLink, and it's more likely to occur on higher resolution displays and/or when playing videos that occupy more of the display area.

dual 4k monitor connected to dell d6000, any laptop connected to this device lags(all drivers updated).