How to turn off both monitors at the same time?

Question

Windows

Two monitors are connected to the video card: one via HDMI, the other via DisplayPort.
When Windows turns off the monitors after the time specified in the power profile, the first monitor simply goes out, and the second one writes on the screen that there is no signal.
How can I make both monitors turn off at the same time?

DELL monitors, MSI GTX660 graphics card

Answer 1

I suppose for this you need to take the same monitors (not just the same manufacturer, for example Dell, but exactly the same). In fact, both monitors do not remove power when they are turned off by software (i.e., video signal is removed), but go into hibernation, and the difference in how this process looks is due only to the software stuffing of their controllers. If it is the same, then there is no reason for non-simultaneity.
However, if they have their own on-screen menu, then the difference may also be due to the difference in these settings.
Can you tell me why such a strict simultaneous damping is needed? I don't think it makes any practical sense. I tried to fantasize about this topic, but to no avail.

Answer 2

If the monitors are the same, then try to swap the connection type, what will happen?
It is possible that the scaler reacts differently to different signal sources
Try changing the HDMI cable, it is possible that the disconnect signal does not pass through it