Dell UP3214Q stuck at 30hz over DP!

[AlbanRampon]

Thank you,
You have a different list here...
Supported Display Modes :
720 X 400 70 Hz
640 X 480 60 Hz
640 X 480 75 Hz
800 X 600 60 Hz
800 X 600 75 Hz
1024 X 768 60 Hz
1024 X 768 75 Hz
1152 X 864 75 Hz
1280 X 800 60 Hz
1280 X 1024 60 Hz
1280 X 1024 75 Hz
1680 X 1050 60 Hz
1600 X 1200 60 Hz
1920 X 1080 60 Hz
1920 X 1200 60 Hz
3840 X 2160 60 Hz
There's no 4Kp30 and there's no 2560x1440, most notably.

Looking at this monitor user guide, there's a * about its implementation pages 10 and 11.

* To display 3840 x 2160 at 60 Hz, DP1.2 must be enabled and the DP source’s
graphics card must be DP1.2 certified with MST feature, capable of supporting
resolution up to 3840 x 2160 at 60Hz and its driver supports DisplayID v1.3.

It looks like it is using dual streams to achieve 4Kp60 instead of a single stream, hence why it requires DP1.2 with MST (Multi-Stream Transport). The product is DisplayPort certified, without MST as MST is mostly used to split pixels (daisy chaining displays), not join them up in one panel.
The reason for the different EDID is because of the second part of that sentence: DisplayID. That's a different EDID format.

On page 36, it says it can handle HBR2... That's fast enough to handle a 4Kp60 over a single stream (or it wouldn't be able to handle it across split screens as MST doesn't create any bandwidth).

To sum up, this is unfortunately expected because of the requirements of 4Kp60 for this display don't match what is available on the docking station.

Kind regards,
Alban