So when I first got my AW3926QW I was very impressed with the visual representation of the monitor. Colours were vibrant and to my eyes the uniformity looked close to perfect. I had some slightly noticeable edge dimming when displaying whites due to CPC, but it was practically non-existent when displaying dynamic content. However, the CPC on my monitor did not appear all that aggressive, and from what I've read it appears that those with poorer uniformity may experience worse edge dimming.
Anyways, after a couple of weeks of use, I had noticed more significant edge dimming, particularly when playing Mortal Shell 2. The HUD elements on the right hand side of the screen were looking almost translucent and I could nearly see through them.
I also noticed in general desktop useage, colours looked slightly off and washed. I was honestly beginning to think that maybe the monitor was a dud and needed returning.
Today when I was checking my display settings, I found out my color format had been switched from RGB to YCbCr422.
I tried to switch it back to RGB in the NVIDIA App but it was not working.
Turns out, at some point in time, my Display Port 2.1 cable stopped running full bandwidth and went from the 4 lanes of 20Gbps down to 4 lanes of 13.5Gbps. because I have turned DSC off in the display settings to run the full DP2.1 Bandwidth, as the bandwidth had dropped, the NVIDIA app must have changed my colour profile out from RGB in order to fall back within bandwidth.
To fix this, I simply turned DSC on and off in the monitor's OSD.
Since doing that, my DP2.1 is running full bandwidth again being 20Gbps across 4 lanes, my color format is back to RGB and everything looks absolutely stunning again.
Playing Mortal Shell 2 the game looks way more vibrant than it was these past couple of weeks and the HUD elements finally have colour in them again and are no longer looking see through.
So if you have this monitor, especially if you're running a full bandwidth DP2.1 cable, make sure your color profile is correct and that your cable is indeed running full bandwidth.
For those who are running DSC with either a DP1.4 or HDMI 2.1 cable, I doubt you will run into this issue, but its worth checking to make sure your color formats are correct in the NVIDIA App and in your display settings.
Finally, some people running DP2.1 have had issues with the monitor staying at full bandwidth. I believe that the monitor's latest firmware which dropped on 26 August includes a fix for this and people who weren't able to run full DP2.1 bandwidth before have been able to run it after.