Why does the second monitor crash after the computer is idle?

Question

Monitors

I have two monitors, a Dell LCD, and a Philips CRT. Win8.1 system. Set to work in extended desktop mode on two monitors.
If you leave the computer idle, after a while they both go out. If after some time, say 10 minutes, the monitors are taken out of sleep, then everything is fine. If you turn it off for an hour, and then turn it on, too.
But if you turn off the monitors (without turning off the computer) in the evening, and turn them on in the morning, then both monitors will have the same screen.
Why can this be so, and where to look to understand the causes and eliminate them?

Answer 1

dig in the direction of your video card, change the driver.