I need to start up and run a 15 monitor setup and I've gotten it to work before but now the screens just flicker. I made sure that my 3 RX 580s were not in cossfire and all the drivers are on the Radeon 18.2.1 update. Each display port output has to have a DP to HDMI adapter and DVI to HDMI Adapter. 15 Asus 1080p 60hz monitors on a video wall all in extended desktop. Threadripper 1900x, 16gb Ram, 250gb Samsung ssd, 1200W PSU.