Precision 7560 and WD19DCS not seeing external monitors Windows 10

hey - thanks for your info. So far I've tried BIOS 1.4, 1.5, 1.7, and today 1.8. None of my display ports on the dock work; while USB 3.1 Gen1 ports do.I unplug the dock from the laptop and from it's power after every driver change.

Also updated bluetooth and assorted drivers as recommended by diag. tests.

Apparently 1.6 was working before my "auto update" (my mistake) to 1.7, but the 1.6 download is not available.

there have been a few times in the six months I have to unplug the dock due to USB or ethernet port not working.  i have not had issue with two external monitors (one on HDMI and one on Displayport).  Been on 1.7 since release. But I think the issue was 1.6.1 or 1.5.0.

Today they released 1.8.0.  

Try just one display if you have not already.  Try with the laptop lid closed to.  You can try disabling hybrid graphics in the bios and see if the DP works.  Also try uninstalling and reinstalling the drivers.  

I have not installed 1.8.0 yet and still on 1.7.0.  I have been using with hybrid graphics off.  I enabled hybird graphics the other day and lost the HDMI and DP audio to my external monitors (only the realtek laptop audio works). I disable the Hybrid graphics and the audio is back.  I have not tried uninstalling the Nvidia and Intel video drivers and then install in order with intel first and then nvdia.  

Tried the one display thing, lid closed and open. Disabled hybrid graphics. All no change = No video of any kind out of any of the video ports on the dock.

There are nine Video "drivers" on this system; though I think 2 of them are overlaid applications. Dump them all? Just intel, just NVDIA, what order - which is apparently significant.

Could it be that your DP cable is bad?  Have you tried another DP cable?  Does your monitor support HDMI and if so have you tried that?  Have you tried switching your monitors and use the USB-C to DP on the other monitor to rule out that it is not an issue with the DP port on the monitor?

Have you tried the mDP on the laptop and not using a dock? Before I got my dock I had two monitors hooked up via mDP and HDMI out of the back of the 7760.

In my Device Manager under Display Adapters I only see two listed.  The Intel and the Nvidia.

I am running the Nvidia drivers from the Dell Support site, not from Nvidia download page.

Thanks again for the ideas. I'm using 2 monitors that are 4K; one using USB 3.1 gen1/2 type C, and the other using HDMI. Single monitor tests of both monitors, also tried using Display Port 1.4. Every test involved removing power from the dock first. All of this worked with the Dock after I initially installed it in January.

In between working this, I plug these same cables and monitors directly into the laptop and all works fine.

Drivers and downloads.link and select check for updates shows odd things:

Skipping the Control Application for NVIDIA and Intel Graphics -

NVIDIA Quadro Px000/Px200/Tx000/RTX x000/RTX 3080 Graphics Driver (needs update-according to this tool, but the version in the EXE name is the same as listed in Sys Info below)

Intel UHD/Iris Xe Graphics Driver

NVIDIA Quadro Series Graphics Driver [3 times with Jun, Jul, Aug 2021 dates]

The following Video drivers are shown in System information - components/display:

Intel UHD Graphics V 30.0.100.9955

Citrix Indirect Display Adapter V 12.40.44.247

NVIDIA RTX A400 Laptop GPU Version 30.0.14.7288

If I ignore the DELL tool results and just look at the Sys info - this makes more sense. Ignore the Citrix. Uninstall the Intel UHD and NVDIA drivers and reinstall in that order.

Latest update from "Engineering"

"Hi, a BIOS update is expected in the coming weeks. The engineering team has suggested you to stay on the older BIOS for now."

Mine has never worked. It charges my 7560 slowly and allows on/off from the dock button, but it won't even recognize mouse/keyboard much less an external monitor.