I have Intel Pentium G5400 with UHD 610 and GeForce 1030.
Function iGPU multi-monitor activated.
If primary adapter (in BIOS) is CPU Graphics, then all work fine.
But if primary adapter is GF 1030, and secondary is iGPU, then Intel Graphics work with error. I explain: when monitor go to "stand by" mode, then after "wake up", on iGPU i see only black screen.
OS Win 10 (1909). MB Asus H310M-K R 2.0.
By the way, Asus tech supp says, that problem may be in MS Windows 10.
You are saying the monitor connected to the iGPU will behave differently (i.e. can be awoken or not) depending upon which GPU is primary?
What about the opposite case (the monitor(s) connected to the dGPU)? Can they be awoken regardless?
This is a good datapoint and hopefully will help the development team with their debug.
To help further, please download and run the Intel System Support Utility for Windows and upload and attach the log file produced to a response. Use the paperclip icon to bring up the upload and attach dialog. Intel Customer Support will take over from there...