Dell D6000 - Screen Flickering

[gafortiby]

Originally Posted by nicola

Hi,
I'm now using StarTech Docking Station with USB3 (no USB-C) since several months and it's running fine with 3x HP 27" screens.

At the end all my "flickering" problem were related to ASUS hardware in relation with USB-C port (ASUS support told me that this notebook officially supports ONLY 1 external screen).

Maybe other brands do not have the same USB-C problem, but using USB3 I solved my problem.

I just wanted to say that I have a Dell D6000 dock, paired with my Dell Latitude 7490. I had exactly the same problem you described, where the monitor connected to the HDMI port would flicker even though the monitor, cables and laptop were fine.

I have also connected the laptop to the dock via its USB-C connection, and two monitors via the displayport, and 3rd monitor using the dock's HDMI port. As the tech support person mentioned, the HDMI port uses the special USB-C alternate mode which means it's driven by the Laptop's internal graphics card and something special in the dock that is NOT displaylink but a different technology.

In this setup, the monitor connected to the HDMI cable would constantly flicker. ONLY that monitor would flicker, all other monitors including the laptop's internal screen would be fine. At some refresh frequencies (Hz) the flicker was like a strobe light. At other frequencies it would just flicker the bottom half of the monitor. Either way the monitor was completely useless.

After the most recent Firmware update (June 2019) of this D6000 dock, provided on the Dell website that the tech support person mentioned, the flicker appears to have completely disappeared. I will report back if the issue comes back, but it appears to be fixed.

If anyone reading this is updating the firmware, be aware that for the flicker to disappear, you have to power cycle the dock AND you have to reboot your laptop. I'm not sure why but simply un-plugging and re-plugging the dock was not enough after the firmware update. A complete reboot was necessary for me.