Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

bballers29

macrumors member
Original poster
Mar 10, 2014
76
93
Hi! I just got the new Air and was wondering if I could use my late 2012 21.5 inch iMac as an external monitor? I think the iMac has 2 thunderbolt ports so would I just need a USB-C to Thunderbolt adapter? Would Apple's Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter work for my situation? Thanks!

 
I believe you should be able to do that, using Target Display Mode (TDM), which is supported by iMacs made between late 2009 and 2013. You'd need a Thunderbolt-to-MiniDisplayPort cable for it to work - I ordered that cable from Amazon. I've tested - no other type of cable worked with TDM. It works with my MB Air and Mac Mini. I've a Late 2009 27" iMac.
 
  • Like
Reactions: bballers29
I don't think you will be able to do this because of the limitation of the Mac that is trying to use the external display.


"The other Mac that you're connecting it to must have been introduced in 2019 or earlier and have macOS Catalina or earlier installed."

See the support page from Apple...

 
I don't think you will be able to do this because of the limitation of the Mac that is trying to use the external display.


"The other Mac that you're connecting it to must have been introduced in 2019 or earlier and have macOS Catalina or earlier installed."

See the support page from Apple...


I think that page is outdated; it was published in May of 2021 and probably hasn't been updated since. I'm currently using Monterey on my MB Air and I'm able to use my iMac as an external display using TDM without issue.

The main requirement is that the iMac needs to be within the build years of 2009 and 2013 - anything outside of that range will not have TDM support.
 
I think that page is outdated; it was published in May of 2021 and probably hasn't been updated since. I'm currently using Monterey on my MB Air and I'm able to use my iMac as an external display using TDM without issue.

The main requirement is that the iMac needs to be within the build years of 2009 and 2013 - anything outside of that range will not have TDM support.
Good to know! I have an older iMac but thought this wouldn’t work with newer macs, might give it a try!
 
I believe you should be able to do that, using Target Display Mode (TDM), which is supported by iMacs made between late 2009 and 2013. You'd need a Thunderbolt-to-MiniDisplayPort cable for it to work - I ordered that cable from Amazon. I've tested - no other type of cable worked with TDM. It works with my MB Air and Mac Mini. I've a Late 2009 27" iMac.
Hello - can you give me the reference of your cable? I am in France and I am not sure which one is it.

Thanks!!
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.