Dell UP3214Q stuck at 30hz over DP!

[AlbanRampon]

Hello Richard,
That is peculiar: the monitor does NOT show 4Kp60 as supported in the monitor EDID information.
Here is the exhaustive list of mode reported supported:

EDID DATA (v1.4)
=========
Monitor Type : DEL4093 (DELL UP3214Q)
Monitor ID : K3R904B2288P
Manufactured : 2014.45
Serial Number: xxxx

Display Parameters
==================
Input type : Digital
Color bit depth : 10 bits per Primary Color
Video interface : DisplayPort is supported
Max image size : 70x39cm (31.5" diagonal, 16:9 ratio)
Gamma : 2.200

[...]

Range Limits
============
V Rate : 29 - 75 Hz
H Rate : 31 - 140 KHz
Max Clock Rate : 300 MHz
No secondary timing curve

Preferred Mode : 3840x2160x24@30

[...]

Display Modes
=============
640x480x24@60
640x480x24@75
720x400x24@70
720x480x24@60
720x576x24@50
800x600x24@60
800x600x24@75
1024x768x24@60
1024x768x24@75
1152x864x24@75
1280x720x24@50
1280x720x24@60
1280x800x24@60
1280x1024x24@60
1280x1024x24@75
1600x1200x24@60
1680x1050x24@60
1920x1080x24@24
1920x1080x24@50
1920x1080x24@60
1920x1200x24@60
2560x1440x24@60
3840x2160x24@30

-> 1 extension blocks present
-> Extension 0 : 02 : EIA/CEA 861 standard Timing Extension block is valid
Checksum Valid : 0xa3


Could you cross-check the monitor settings? What type of cable do you have between the dock and the monitor? (connector type on each end) The reason I'm asking is the EDID is consistent with HDMI 1.4 so used with HDMI or DP++ modes.
4Kp60 would be higher than the advertised max clock rate of 300MHz. So both are consistent.
Unless the EDID allows higher, we won't try higher.

Kind regards,
Alban