I've tried 3 MG279Q on my other rig which has a Sapphire Toxic HD 5850 and there is no display output when connected by DP. Will test other connections, anyone else with similar issue?
I believe the GPU has no issue as it will work on an Eizo FG2421 & Dell U2515H using DP.
I know the DP on the 3 MG279Q work as my Fury X displays output on the screens. The testing is with a screen at a time.