Good day! I have a RADEON PRO WX 4100 graphics card and a Samsung U28E590D monitor. Drivers are used the latest version. I can’t set 4K resolution on the monitor. The maximum possible is 1920 x 1080. When I try to configure in manual mode, an error occurs that it is not possible with my monitor. If I use the integrated Intel card, I can set the resolution to 4K.
Given your video card supports DisplayPort 1.4 you should have no issue using it to achieve 3840x2160
cables may be a problem, DisplayPort needs quality cables to handle the higher bandwidth needed
How are you connecting the GPU card to the monitor?
Are you using an adapter by any chance?
What does Windows Settings - Display show as far as resolutions?
What does Device Manager show? Any Yellow exclamation marks or errors showing?
I have an Acer Monitor that has a higher resolution than 1920x1080. But with HDMI connected I wasn't able to reach to higher Native resolution shown in Windows Display. When I clicked on the higher Resolution it would go black. But I was able to get the higher Resolution using DisplayPort cable.
But depends on the GPU card and Monitor you have installed. I know you can get HDMI 4K now.