P2715Qt - Monitor will not wake after PC sleep

I would remove the docking station from the troubleshooting equation. The Latitude E7270 has an HDMI out port and a mDP out port. I would test in this way =

* Latitude E7270 is in sleep mode
Latitude E7270 mDP out port --> mDP to DP cable --> #1 P2715Q DP in port
Latitude E7270 HDMI out port --> HDMI to HDMI cable --> #2 P2715Q HDMI in port
* Wake up the Latitude E7270. What are the results?

I have the same issue (E7450, Standard Port replicator and a P2715Q).

If I connect the mini DP to the monitor directly it wakes up. Its just through the DP on the docking station that does not work. I also have a P2417H that behaves the same.

I've swapped cables, updated bios, and intel and nvidia drivers from dell website.

Any other ideas?

Based on your testing, you have isolated the docking station as the culprit. What specific docking station model, part number? IS there another dock there to test?

I'm not sure of the exact model it looks the same as the E-Port on the website. I could not get the codes on the label to recognize it.

Reg type - K07A002

DP/N WV7MW A02

I will contact my IT department to see if they have another for diagnostics.

I think that WV7MW K07A002 is the ePort II Pro3X. Does yours match this one?

If yes, can you test a DP to DP cable?

Yes, that's it. I was also given the 'plus' version of that station to try (it has two sets of video outputs and some serial ports etc as well. I get the same on both stations. I even bought a new DP cable to try. And also tried the miniDP input on the monitor. its always the same.

I did try my original docking station in the office with a P2715Q there and it seemed to work. Maybe there is a setting I have missed on the monitor?