I’m trying to get 3840×2160 60hz to work on my Mac Pro 2013. I can get 60hz working up 2560×1440, but not higher. I can see the option in SwitchResX, but when I switch, the screen goes black.
Screen: Samsung LU28E590DS
Card: Dual AMD FirePro D700 6 GB
MacOS: Mojave 10.14.5 (18F132)
HDMI cable: UGreen Premium Certified
Anyone else having this problem, and/or know a fix?