Hi I've have recently invested in a new Dell OptiPlex 7070 i7 workstation. It currently has a AMD Radeon RX 550 graphics card installed which i plan to take advantage of and use. I can't figure out how to run my monitors at UHD (4K) resolutions though. In windows the maximum resolution option is set at 1920x1080. I cannot select a higher resolution and it dosen't give me a higher resolution option to select in display preferences. I know my MiniDP to HDMI adapters and HDMI cords are 4k compliant - I have success at running 4k to my monitors (Samsung U28H750UQE model - 4k monitors) on other systems using the same set up, the same cords and adapters. So i know it's not the cords or adapters that are causing the issue. I have tried installing the latest drivers and software aswell as rolling back the driver using the clean install technique. I have spent quite alot of time trying to figure out what the issue is. Any help would be kindly appreciated.