rMBP driving 4K iMac

[trms23]

Hey forum!
I wanted to ask you, why a Macbook with Thunderbolt 2 equipped can't drive the new iMac 21" Retina in Target Display Mode Theoretically Thunderbolt is capable of driving 4 Monitors. Why's that impossible here?

Regards

 

[cariacou]

cause Apple blocks it. I'm guessing they're working on a thunderbolt 4k/5k monitor and don't want the iMacs to mess up the release?

 

[theosg]

Um, Apple didn't include Target Display Mode on 4k 21" iMac or on 5k 27" iMac.
So there's your problem...

Or, if you knew that already, one common observation is that Apple loves to gradually solve issues and dole out those solutions. They seemingly haven't solved some issue with Target Display to their satisfaction. What else can be said?

 

[trms23]

It's just weird. Either they're working on a new Thunderbolt Display (hopefully) or Thunderbolt 2 is to weak to drive the iMac 4K

 

[mtneer]

I vaguely remember reading something about Apple using a custom timing controller for their retina iMac screens that precludes them from being used in target mode.