I saw a thread a bit ago which referenced issues with 5700 XT vid cards and Samsung CHG70 monitors (although other Samsung users also responded with similar issues...). I'm having issues too although slightly different so I thought I would post them here as well in a new thread to raise the awareness at AMD about this.
As I said below, be sure to file a problem ticket with AMD for any and all problems you are having. That can be done here: https://www.amdsurveys.com/se/5A1E27D23A3DE966
The two issues I am directly seeing:
- When I leave BF5 while playing the game in HDR and have the monitor Freesync mode set to 'Ultimate Engine', everything appears to be a bit dark. I have to go to Window's display settings and toggle HDR ON then back to OFF to get everything back to normal. Annoying but there is a fix. The good news I've found this issue goes away if Freesync is set to 'Standard engine' in the monitor settings. I could live with this if the following, second issue wasn't happening...
- It appears if I leave my system running for a bit then play a game, the monitor goes crazy bit. The screen will go in and out. Eventually, it may/may not go totally black. When this happens, sometimes I can change the Freesync mode of monitor and everything corrects itself, but not always. Sometimes I can cycle power on/off for the monitor and this resolves this, but again not always. Sometimes I can hit CTRL-ALT-DEL and kill the game and that fixes everything, or do something to get back to the desktop such has hit ALT-TAB. Sometimes, I can't get back to the desktop at all as the screen goes black and stays that way. I have to power cycle the PC when that happens which is not good as you can imagine (notice the system does not crash nor have I seen it do that!!). After playing around with this, I think the problem occurs after the monitor goes to sleep which happens on my system after 10 minutes of inactivity. I have not been able to replicate the problem as long as the monitor does not go to sleep.
I had neither problem above with my Vega 64. I am currently using the reference 5700 XT.
Again, as mentioned, be sure to submit a problem ticket to AMD to get these problems resolved if you like me you are seeing them. If we bang AMD upside the head enough, we'll grab their attention.
I hope. 
Thanks,
Chris Smith
