Linking iMac mid 2011 as an extended display for MacBook Air 2025 M4

How can I connect my MacBook Air 2025 M4 to use my mid 2011 iMac 27inch, macOS High Sierra as an extended display screen?


Specs of iMac - 2.7ghz Intel Core i5

Start up Disk 04

Graphics AMD Radeon HD 6770M 512MB

Serial No C02JF2G*****


Can I use a Thunderbolt adapter converter from Thunderbolt 2 to 4?

Use a DA - display adapter


Advice?


Please email me at la****@gmail.com.


[Edited by Moderator]

Posted on Sep 22, 2025 9:41 PM

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Question marked as Top-ranking reply

Posted on Sep 23, 2025 1:23 AM

Although both the 21.5" and 27" Mid 2011 Macs support Target Display Mode using Thunderbolt input, you can't use your iMac as a Target Display for a M4 MacBook Air.


Apple added restrictions to Target Display Mode that mean that no Mac released after 2019 and no Mac running anything later than Catalina supports using any iMac as a Target Display.


According to both of those tests, your M4 MacBook Air is too new to support using any iMac as a Target Display.


See the bad news here: Use your iMac as a display with target display mode - Apple Support


Given that, it's not worth spending $80+ on specialized Thunderbolt connection hardware that probably won't be enough even to let you use the iMac as an unsupported display. Put the money towards a real standalone monitor.

2 replies
Question marked as Top-ranking reply

Sep 23, 2025 1:23 AM in response to tyler_oscar

Although both the 21.5" and 27" Mid 2011 Macs support Target Display Mode using Thunderbolt input, you can't use your iMac as a Target Display for a M4 MacBook Air.


Apple added restrictions to Target Display Mode that mean that no Mac released after 2019 and no Mac running anything later than Catalina supports using any iMac as a Target Display.


According to both of those tests, your M4 MacBook Air is too new to support using any iMac as a Target Display.


See the bad news here: Use your iMac as a display with target display mode - Apple Support


Given that, it's not worth spending $80+ on specialized Thunderbolt connection hardware that probably won't be enough even to let you use the iMac as an unsupported display. Put the money towards a real standalone monitor.

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Linking iMac mid 2011 as an extended display for MacBook Air 2025 M4

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