750Ti + MacMini 6,2 + inject nVidia = 4k @ 60hz, but just one port is working.

Nov 20, 2010
ASUS ROG Strix Z390-I Gaming
RX 5700
MacBook Pro
So here's the deal. I have a GTX 750 Ti. Back when I was in Yosemite, I used the nVidia web drivers and the MacMini 6,2 sysdef workaround to get 4k resolution @ 60hz in my MST dell monitor. It worked beautifully. But now I upgraded to El Capitan, and the workaround doesn't work anymore. When my monitor is set to DP 1.2, all I get with the exact same configuration is a black screen (if I set the monitor to DP 1.1, everything works, but @ 30hz).

BUUUUT, I noticed that if I inject nVidia in Clover, DP 1.2 works and I get that pesky 4k @ 60hz (same MacMini 6,2 sysdef). Everything works good enough for me, except for the fact that if I inject nVidia, only one port of the card works. If I have the DP connected, then it's the DP. But If I connect anything to the DVI, then just the DVI works.

So my conundrum is basically: if I don't inject nVidia, I have all the ports working but only 4k @ 30hz since DP 1.2 refuses to work. If I inject nVidia, DP 1.2 works and I get the 4k @ 60hz, but only one port of the card works.

I'm still curious on what is it that inject nVidia does that makes DP 1.2 work, but I can live with using inject nVidia. My question is, is there something I have to do to get the other ports working? My 750 Ti has one DVI, 2 HDMI and one DP.

Thanks in advance!