5K monitor seen as two displays

[mchis]

Okay, so it's a about the pretty-new Philips 5K (i.e. Brilliance 275P4). Imho it's better from a hardware point of view than the Dell UP2715K with whom I had huge color issues (white balance mainly) as well as it heated up like hell, hence my attempts to try and make it work. Trouble is, OOB it's seen as 4K only, two displays...

Summary:
- Clover boot args contains nv_spanmodepolicy=1 (and of course the nvidia driver is used)
- Tried with various DP cable configurations; my quess is however that port 1 is the one that's closest to the MB slot (ASUS graphics card manual does not specify that).
- Tried with turning the monitor on and off, power cable on and off
- Tried with turning the monitor on only when the OS was loaded
- Tried with creating a display override mtdd file, i.e. DisplayProductID-8f4.mtdd in /System/Library/Displays/Contents/Resources/Overrides/DisplayVendorID-410c. This file is basically the HP Z27q one (which is supplied by default in El Capitan) with EDID, product id, vendor id changed accordingly

Still, the monitor is always detected as two displays, 4K maximum capability. I suspect multi-stream transport is not activated...

Any help would be appreciated!

Michael

 

[mchis]

OSX is El Capitan, 10.11.5, and the nVidia drivers are at the latest version. I have also updated the Clover bootloader to the latest version i.e. 3577.