target display mode (not working)
I have 2 iMacs (2017 21.5 quad core i5 4k) and (2013 21.5 also i5) --- I purchased a cable that was thunderbolt 3 on one end and thunderbolt 2 on the others --- pressing command F2 or Fn-command-F2 didn't work. Both iMacs have High Sierra OS installed.
I checked the hardware settings and neither thunderbolt port is on or enabled when plugged in. I tried both ports on each iMac and also rebooted -- nothing worked.
I thought the 2013 iMac was able to support target display mode --- what am I missing or doing wrong?