My issue is twofold:
So I bought a new monitor recently, a Samsung 49CRG9 which is a dual QHD screen (5120x1440). When I first connected the display-port to my Vega 64 I got an output on the screen that looks like many horizontal lines in different colors (scrambled). After a while this turned to the entire screen giving a dark orange glow. Not being able to do anything with the computer like that I tried the HDMI connection. Thankfully that connection worked but now I don't have the benefit of Free-sync 2 (the 2nd reason I bought the monitor).
At first I thought the issue was with the monitor so I contacted the vendor that my display-ports were defective. So I returned the monitor and received a new one after a week. I was greatly disappointed when the 2nd monitor display-ports did not work either. The ports do work with another screen that I own - with a 1920x1200 resolution - so it can't be the cable right?
Though HDMI works I am having a few issues with it. Every time the computer goes into its sleep state and I reactivate the computer the resolution reverts to 1920x1080. The only way I have found to change it back to 5120x1440 is by starting Radeon-Software, selecting the Monitor tab and clicking the Scale with GPU tab. It does not matter if the tab is active or not. Clicking it once will bring me back to a 5120x1440 resolution. So I performed a test by turning the monitor off and waiting for the computer to go into the sleep state. Strangely even with no monitor active the same thing happens, i.e. the resolution reverts to 1920x1080. So it must be an issue with the AMD graphics card right?
Anyway since I want to use the display-port connections the HDMI behavior is not my primary issue as annoying as it is. I need the display-port to work. I have no clue as to why it is not working. Is it the monitor or is it AMD graphics?
I hope someone can help.
NB Find attached 2 screenshots of the screen.
I forgot to mention that I tested the AMD graphics card display-port on a different screen (native resolution 1920x1080). On that screen the display-port from the Vega card worked. All three ports.