Using an older iMac (2013) as a monitor for a new iMac(2020) ---- how do I do It?
iMac 27″, macOS 10.12
It cannot be done, the new iMac needs its own external display. Big Sur was the final nail in the coffin of Target Display Mode and no you cannot install an earlier version of Mac OS on your new Mac and no there are not any work arounds. There are third party wireless solutions, however, I cannot vouch for how well they work.
macOS Big Sur and 2020 Mac releases killed off this functionality. Sorry.
Cheers,
Jack
I have a iMac 27 " late 2013 that I would like to use as a second monitor for a new iMac 27" I just purchased ...... what is the best way to do it??
