Level 1

4 points

Using old imac 27 as second screen to new 24” imac

How do I connect my iMac 27″ 5K macOS 13.6.3 as a second screen to my new iMac M3 8 core cpu 10 core GPUv24” macOS 14.4.1? (The 27” is a working computer but is very slow. )

I get the following error message when I try connecting them: “Carnot use Thunderbolt accessory- connect accessory to a Thunderbolt port on this(24”) Mac,” which is where it is.Moving the cable to any of the remaining ports doesn’t connect either.

Do I need a Luna adapter or something similar?

iMac (M3, 2023)

Posted on Apr 2, 2024 11:19 PM

Reply

Top-ranking reply

Level 10

181,236 points

Posted on Apr 2, 2024 11:32 PM

you can't using the old target display mode both the 27" and the 24" are way to new for that to work

Use your iMac as a display with target display mode - Apple Support

but there are other ways Use iMac as monitor: 5 Solutions - 9to5Mac

but getting a standalone 27" monitor would use a fraction of the electricity of the old full computer imac acting as display

View in context

Similar questions

1 reply

Top-ranking reply

Level 10

181,236 points

Apr 2, 2024 11:32 PM in response to Chym95

you can't using the old target display mode both the 27" and the 24" are way to new for that to work

Use your iMac as a display with target display mode - Apple Support

but there are other ways Use iMac as monitor: 5 Solutions - 9to5Mac

but getting a standalone 27" monitor would use a fraction of the electricity of the old full computer imac acting as display

Reply

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

Using old imac 27 as second screen to new 24” imac

Welcome to Apple Support Community

A forum where Apple customers help each other with their products. Get started with your Apple Account.

Learn more Sign up