For anyone having this issue regularly, can you let me know if you have 2 displays hooked up to the system? This can be 2 AW3423DW's or 1 AW3423DW and another non-matching monitor. Or if anyone is only using this monitor as the only display hooked up to the system?

Also, regardless if you have if you have 1 display or 2 displays in use, can you turn off Auto Select on the AW displays and manually select the Input (DP or HDMI) and let me know if that changes anything? I have been relaying this info to the display team and recently helped with an AW3423DW with a non-Nvidia card setup that seemed to correct the blanking problem by turning off auto select for the inputs on the monitor, unfortunately this did not work on another system that was using an Nvidia card when I tried to retest this, but wanted to share in case. This might have been an entirely different issue but fortunately seemed to help, so I wanted to know if it was tested by anyone yet.

If you would like to try something else that might help as a workaround for now and you're using dual non-matching displays, please see if turning off G-Sync within the GeForce menu changes anything with regards to the monitor blanking out/not waking. I know this is not a solution but wanted to see if anything changes with the symptoms on the monitor.  

Lastly, if you have 2 matching AW monitors, can you let me know if you're using surround mode within the Nvidia Control Panel? And if not, please enable that?

Please note, I am only wanting to see if this changes the behavior of the monitor and will relay this to the Display Team. If anyone has already tried these steps or has questions please let me know.

When replying/providing updates please let me know the video card that is currently being used, and number of monitors hooked up to the system when you're having this occur. Please let me know what state the system is in (gaming or just on desktop etc.).  I know there's a few things being discussed on this thread, so if it's only sleep related, starting with turning off auto select and manually selecting the input might be worth trying first. 

Sorry you're having this issue, it sounds like this one might be a bit different since it is happening in BIOS. What video card are you using and how often are you seeing this occur? 

Also, when it happens while in the BIOS what do you have to do, unplug the monitor to get it to come back? And what state is the power LED in when this happens? 

Thanks for the heads up, let me know if anything changes. If not, please try the next step of disabling the G-Sync in control panel. I just want to see if it isolates the issue/changes symptoms etc..  

Thanks for the update, also, what GPU are you using?

Thanks so much for testing this, please keep me posted.

Thanks for the callout on the HDR, I have been thinking about this as well but have not tested this yet. 

On a side note, do you still have the S3220DGF? I still have that one and know what you're talking about (at least on issue I had with it blanking out), the fix on earlier FW versions was to adjust the lowest refresh rate allowed (iirc you need to up the the rate to 45 or even 50 for the min), I can't recall at the moment what I ended up with but know it fixed this, this is just for the earlier FW versions of the monitor and if you're trying to use G-Sync. At the time I had a 1080 too and also did the FW update for DP 1.4 on that card. Here is a Reddit thread that discussed this back then but I don't think it will help here. 

With that said, if you don't notice the issue comeback please keep me posted, and if you do notice it come back and want to test this further go ahead and turn off G-Sync in the Nvidia Control Panel, that's the one workaround that has been somewhat consistent with a few of these, but I am still trying to confirm it actually prevents the monitor from blanking out. I realize this is not a solution but wanted to share any of these results directly with the Display team.

Unplug the monitor's power cable, press the power button on the monitor with it unplugged (hold 5 seconds or so then release), plug the power back into the monitor and let me know if it comes back. Hopefully the power button illuminates at a minimum. The setting changed should not have prevented the monitor from responding to pressing the power button.  

I hope this helps.

Sending you a PM! 

Sorry to hear this didn't work and thanks so much for trying.

Can you let me know how often you're seeing this with normal use (I guess before making the change with G-Sync)? Like every time the monitor is sleeping? Also, since you have multiple monitors, can you let me know if changing the refresh rate/resolution on the AW monitor if it will force it to wake up? I have had a one off situation where a monitor was actually still showing up vs being locked and having to be unplugged etc.. Just trying to get an idea and share this with the Display team.