I have 2 iMac m1 24inch 2021 and a got a Thunderbolt 3 cable. I was trying to use the second iMac as my second display, but when I put option F2 nothing happens. Any suggestions to make it work? I have already checked the resolution and the software version. I checked the cables and they are on the thunderbolt ports on the back. Any suggestions?
iMac Line (2012 and Later)
You are trying to use Target Dispaly Mode (TDM) and that is dead tech. The very limited hardware requirements for TDM are in this Apple support article:
Use your iMac as a display with target display mode - Apple Support
No M1 Mac scan be the video source even if your old iMac was one of the very few that supported acting as a monitor for another Mac.
This is the article's pertinent part that explains your inability to make this work:
Also, only a small number of iMacs made between 2009 and Mid 2014 were TDM-capable. Apple started the deprecation of TDN in Late 2014 and threw the last shove of dirt in its face in early 2020.
You are trying to use Target Dispaly Mode (TDM) and that is dead tech. The very limited hardware requirements for TDM are in this Apple support article:
Use your iMac as a display with target display mode - Apple Support
No M1 Mac scan be the video source even if your old iMac was one of the very few that supported acting as a monitor for another Mac.
This is the article's pertinent part that explains your inability to make this work:
Also, only a small number of iMacs made between 2009 and Mid 2014 were TDM-capable. Apple started the deprecation of TDN in Late 2014 and threw the last shove of dirt in its face in early 2020.
That will not work, your iMacs are computers they are not displays for other devices. Please refer to Target Display Mode. If you need or want an external display please buy one and return the expensive cables you bought which will pay for the majority of the cost of an external display.
two imacs and dual display
