I've had my 6900 XT for around half a year. I'm late tackling this issue, as it's been misbehaving for that whole time.
The first thing I noticed right after installing was this weird horizontal, green colored glitchy line sometimes appearing at the bottom of my monitor when gaming on a very demanding game (KCD). Apparently that's due to insufficient power - well #$!*. These also appeared in other way less demanding games like Overcooked. At some point they disappeared and now I never see them.
The second thing I noticed was crashes. For 6 months it's been very infrequent, for the past week it's been several times a day. The only game that's been causing me trouble there is WoW. I noticed its fullscreen mode isn't really fullscreen and there's no real way to make it actual fullscreen so maybe that's the reason? Maybe 1 out of every 50 alt tabs will cause a crash. Sometimes it recovers, sometimes it causes a reboot. Interestingly, clicking on "Start Discussion" here with WoW running behind caused a crash. It's like it's out to get me.
The third thing is glitchiness with VLC and youtube. Having 2 vlc open on each monitor and switching from one to the other causes white flashes and a mini freeze. Having youtube open and switching to my second monitor makes it flash and freeze too.
Crucial Ballistix 32 GB (2 x 16 GB) DDR4-3200 CL16
Corsair RMx (2018) 850 W
M27Q monitor (DisplayPort) + generic 1080p monitor (HDMI)
GPU and CPU not overclocked, PSU cords are 2 separate, not 1 daisy chained
Latest drivers, latest bios flashed, no MSI Afterburner but RTSS running at all times
170hz freesync monitor, most apps capped to 167fps with RTSS
I don't keep an eye on temps but they are sitting at 66°C right now on WoW
End of specs ---
What can I do to make this better? Please halp :3
You are right on the limit with an 850w PSU, that is the min recommended.
Is you card an AMD reference card or Sapphire, MSI etc.
Oh yes sorry it is an AMD reference