Dell U2312HM The current input timing is not supported by the monitor display. Please change your input timing to 1920×1080@60Hz or any other monitor listed timing as per the monitor specifications.

Is there a setting or some way to keep the HDMI1 input "active" and stay connected as a 2nd monitor when I change to another input?

How do I fix my monitor Input Signal Out of range? To fix a monitor input signal out of range problem adjust the computer’s resolution to a compatible setting with the display.

There's more to setting up your new monitor than taking out of the box. We're here to show you how to set up your new monitor for the best picture possible.