I have an iMac - Retina 5K, Late 2015, 1TB, 3.2GB RAM, 3.2GHz i5, that won't be receiving Os updates after the end on this year. I want to buy a Mac Mini and use my iMac as a monitor. I know I can use it that way, but after support for Montery ends can I still use it for that purpose?
iMac 27″, macOS 12.7
The old Mac is too new and the new Mini is also too new.
Review the document: Use your iMac as a display with target display mode - Apple Support
Target display mode is a feature available with late 2009-Mid 2014 iMacs. The display Mac has to be running macOS High Sierra or older and the signal producing Mac has to be running macOS Catalina (ca. 2019) or earlier.
This could only be done with a very few and very specific older iMacs and support was very limited. Read this topic for a 2021 perspective on this: Using iMac as an external screen - Apple Community
and this 2021 post by Allan Jones about software limitations:
TDM configuration - Apple Community
and read about Screen sharing Share the screen of another Mac - Apple Support
The old Mac is too new and the new Mini is also too new.
Review the document: Use your iMac as a display with target display mode - Apple Support
Target display mode is a feature available with late 2009-Mid 2014 iMacs. The display Mac has to be running macOS High Sierra or older and the signal producing Mac has to be running macOS Catalina (ca. 2019) or earlier.
This could only be done with a very few and very specific older iMacs and support was very limited. Read this topic for a 2021 perspective on this: Using iMac as an external screen - Apple Community
and this 2021 post by Allan Jones about software limitations:
TDM configuration - Apple Community
and read about Screen sharing Share the screen of another Mac - Apple Support
Correct, you cannot (at least in Target Display Mode) for two reasons. The 2015 iMac is not one of the models (late 2009-Mid 2014 iMacs) for which this was possible. In addition, any new Mini cannot run the required older macOS version. Even if you had an old Mini, it still wouldn't work with that model Mac.
I don't know if screen sharing is what you want to do. It sounds like you want to save on buying an additional monitor, not just have a second screen.
So, are you saying I won't be able to use my iMac as a Mac Mini Monitor?
Using my late 2015 iMac as a monitor
