Dell p2715q on MacBook Pro 2016

You'd need a Thunderbolt 3 to Thunderbolt 2 adaptor, and then a mini display port to display port cable, or if such a thing exists a thunderbolt 3/USB-C to display port cable.

 

doesn't work. TB2 adapter doesn't support miniDP. My 4K Dell is worthless without the $70 Apple HDMI adapter. The only thing the TB2 adapter is good for is the TB display.

 

HDMI only works at 30Hz though. You'd need a USB-C/Thunderbolt 3 to DP cable. If none of that is possible, then ebay the monitor and buy one of the new LG monitors that have been designed to work with the MBP. Or sell the whole lot and get a PC - the XPS 15 works just fine with those monitors!

 

I can confirm that a USB-C/Thunderbolt 3 to DP cable works @ 4K/60Hz with the Dell P2715Q. However, I had to disconnect and reconnect the power to the monitor (?!) before the Macbook Pro would recognize it.

This is the cable I used: https://www.amazon.com/gp/product/B01EXKDRAC/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

 

I run dual P2715Qs at 4K60 with these adapters from Monoprice.
https://www.monoprice.com/product?p_id=13234

 

Does it continue to work after the 10.12.5 upgrade? Mine used to work fine but is not working after the upgrade.