New iMac 5K (August 2020) supports Target Display Mode again?

[dukee101]

Since the first 27-inch iMac with Retina 5K display was released in 2014, Apple discontinued Target Display Mode for those models going forward. This was due to various technical limitations that were never overcome -- until today (potentially), with the release of the updated iMac 5K with the new T2 chip.

Does the inclusion of the T2 mean that the iMac 5K can now support Target Display Mode? Is there anything else about the updated iMac 5K that would lead to TDM being supported once more?

I'm desperate for a quality 5K display for my MBP that isn't the LG UltraFine. I am literally willing to pay the money for a new iMac just for the display.

 

[CWallace]

Target Display Mode was dropped because the 5K iMac requires a custom timing controller to drive the display at 60Hz and TDM does not work with said controller.

That hasn't changed since 2014.

 

[dukee101]

Target Display Mode was dropped because the 5K iMac requires a custom timing controller to drive the display at 60Hz

Exactly. My question is whether the custom timing controller has been subsumed by the T2, which may potentially be able to interface with the Thunderbolt 3 bus, driving display input on those two TB3 ports.

 

[CWallace]

Exactly. My question is whether the custom timing controller has been subsumed by the T2, which may potentially be able to interface with the Thunderbolt 3 bus, driving display input on those two TB3 ports.

No, since the iMac Pro has the same display and T2 since 2017 and TDM is not available on it.

 

[Sela Gu]

Hello, are there any new learnings on iMac 2020 with Target Display Mode? Any chance it can work? Anyone tried?

 

[drkknte]

Hello, are there any new learnings on iMac 2020 with Target Display Mode? Any chance it can work? Anyone tried?

Tried and failed multiple times with my 2020 iMac pair with my 2012 iMac on High Sierra and a buddies 2016 iMac on Mojave.

I have had pretty good success with Astropad’s LunaDisplay. The latency is a lot better that Duet, however still not as good as Sidecar.