I've got two monitors in the setup:
Samsung 24CFG70 on Displayport->PC
ViewSonic VA703b on VGA->HDMI Adapter->PC
It started a while ago about two years after I got the Samsung monitor after some windows update. About 50-60% of the time, the Samsung monitor won't get detect or is only half detected on startup from both sleep and cold. On the initial push of the power button, the monitor does wake, but then searches through the inputs before going into standby mode again. The ViewSonic monitor always gets detected.
What I mean by half detected is that w
hile the monitor wakes, loop through the inputs, and even after the monitor goes back to sleep is that the view sonic monitor turns on and shows a black screen as if everything is working fine in extended desktop mode. It's at the login screen at this point. Of course, the login screen is outputting onto the half detected samsung monitor so I have to blindly put in my pass code.
After it logs in, the ViewSonic monitor flickers and then goes into single display mode. If I don't log in and just press the power button on my monitor before to wake it up and it starts looking through inputs again, it also does this. I spammed the detect display button in the settings after logging in while it's like this and nothing is detected.
I've tried reinstalling/updating drivers, reseting the graphics card, using a different pcie slot, changing the displayport cable, and still happening and seems to be getting more frequent but that might just be my luck with the 50/50.
My build:
MSI Z170A Gaming M7
I7-6700K
EVGA GTX970 FTW+
16Gb DDR4-3200 Gskill Trident Z
2TB Hybrid Drive
128GB Sata SSD