2nd monitor question

[dimme]

I have a 2021 24" iMac and occasionally I hook up a second monitor for certain projects. Most of the time I just use the built in display. The second monitor connects through a CalDigit TS3. So for those times I not using the second monitor I usually unplug the DisplayPort connection and turn off the power to the second monitor, to save system resources. I was curious if I really need to unplug the display port or is turning off the power good enough. When it's powered off It does not show up in the System Preferences.

 

[joevt]

If the display doesn't appear in System Preferences then it's not using resources.
Does the display appear when it's powered on again? If so, then everything is probably working as well as can be expected.
Do you have issues with waking from sleep? If so, then maybe disconnecting and reconnecting the DisplayPort might help then.