here's my personal experience regarding this. i got a acer predator XB3 , the same model that was reviewed by TH (https://www.tomshardware.com/reviews/acer-predator-xb273k-4k-144hz-gaming-monitor-hdr,5998.html) and it turns out in order to play some older game that supported HDR you need HDMI so i got a HDMI 2.0 cable. the monitor did not came with one. so games like BF1, mass effect Andromeda, AC Origins, HITMAN, HITMAN 2 demands that you have a HDMI connection in order to enable HDR within the game. on the other hand games like gears 5, SOTTR, FF XV, COD WW II, Metro Exodus are capable of handing HDR via DP connection. so until this BS settles down in gaming industry for anyone out there who have a nvidia card and have a g-sync monitor better make sure to have a HDMI 2.0 cable so you can play the games in HDR if they demand a HDMI connection.