Hello Cowdog,
Thank you for taking the time to report this, and the logs.
From the log files (system_details.txt), it looks like all 3 monitors share the same serial number. So, I need to find another way to follow things through. I see you've got two models Plugable UGA-2KHDMI & Plugable UGA-4KHDMI. Would you be able to check which one is on the sleeping display?
I'd like to understand the state of that display when you recover from sleep/reboot.
Would you be able to leave "Windows display settings" panel open on one of the displays which comes back alive? This is that menu:
https://www.tenforums.com/tutorials/...0-a.html#Part3
When your primary display is staying in power save, do you see it present on the layout?
Last question, I see your machine should have only 2 USB-A ports. Would you please be able to describe how the devices are connected? You can post of photo of the setup to save you from typing!
With Windows 10, you shouldn't have to reboot. Windows can now handle gracefully adding/removing displays within seconds.
Kind regards,
Alban