[waynec_jagsnvettes]

Not sure what happened, but for about a month my second display does not come up when the computer is booted... all my icons are on the primary display and the second screen is not connected/operable.

If I power off the machine, then boot up 3 more times in succession (ie, 4 power-off/power-on bootups in a row), the computer comes up with the 2nd screen operating on the 4th bootup.

If I shut the computer down at any time, it always requires 4 complete power-on bootups to get the second screen operating.

Another symptom, I am not able to do a reboot of Win 10 without powering-down, Windows shuts down but then the machine freezes with the power on and nothing happens on the primary display.

[mtf1380]

I sometimes have an issue with one of my screens not coming on when booting up, or waking from a sleep state (using 3 screens in total, and happens to the same screen when it happens)...I am able to kick start the non-reactive screen by powering that screen off and then powering it back on; has worked every time so far for me.

[waynec_jagsnvettes]

Tried that, many times (and checked what source the display is using), also does not make any difference when or if the second display was powered-on, before or after the computer power button is pressed. I even played with taking all the startup programs off the startup list (msconfig, Startup-open Task Manager)... no effect. The strangest thing to me is the fact that it always takes 4 power-on button/Win 10 boots of the powered-down computer to bring up the second screen.

[waynec_jagsnvettes]

Today Windows automatically installed 2021-04 cumulative update when I powered the computer on in the morning ...as the Windows update was being applied I noted that my second display was active, and when the update was complete and Win 10 came up, I had full use of both screens. But as soon as I shut the machine down and rebooted, I was right back into the routine of having to power-up/reboot 4 times to get the second screen working.
Beats me!

[waynec_jagsnvettes]

Today Windows automatically installed 2021-04 cumulative update when I powered the computer on in the morning ...as the Windows update was being applied I noted that my second display was active, and when the update was complete and Win 10 came up, I had full use of both screens. But as soon as I shut the machine down and rebooted, I was right back into the routine of having to power-up/reboot 4 times to get the second screen working.
Beats me!

RESOLVED!!!! The issue turned out to be a bios setting on my MSI Z97 motherboard. I had re-flashed the motherboard due to a serious issue where I was not able to boot Win 10 at all; the re-flash had fixed the boot issue but apparently it also changed an obscure bios setting pertaining to graphics. I was so fixated on the boot issue that I did not notice the 2nd display issue until days later and didn't associate it with the bios re-flash... since I used an add-on display card rather than the MB display adapter alone, I did not suspect the MB bios.