4K, 3840 x 2160 Resolution (UHD) at 60hz?

[matt2053]

- That's actually not true. Apple has apparently updated the specifications for the adapter, now citing support for 4K at 30Hz.



- That's just plain odd. And Ars even tested it on 10.10.3 (which supposedly brought the improvement)...

I suppose your "we will wait and see" statement still holds.

Yeah I meant 4K at 60 Hz.

Either way, Ars tested the MB while on battery, driving both the internal display and the external display at the same time, so I'm not all that surprised performance was poor. I discussed this with the author of the review this morning and this was what he said:

I updated to 10.10.3 when it was made available and there's no difference as far as 4K is concerned, still no 60Hz/SST support for this Dell display that works fine with the new Airs and Pros, and still relatively poor performance. It's possible that this is related to the internal display – maybe if it was disabled, the external screen could reach 4K? But you'd need some kind of hub or adapter to use the MacBook with an external display while the internal display was off.

 

[ctyrider]

Either way, Ars tested the MB while on battery, driving both the internal display and the external display at the same time, so I'm not all that surprised performance was poor. I discussed this with the author of the review this morning and this was what he said:

I seriously doubt Apple intends an external display to be used only if MacBook is closed.

The MacBook Tech Specs page also states the following:

Dual display and video mirroring: Simultaneously supports full native resolution on the built-in display and up to 3840 by 2160 pixels on an external display, both at millions of colors

Something is seriously wrong with Apple specs and support pages claiming 4K/60Hz support on rMB, where it clearly doesn't appear to work.

 

[JTToft]

Something is seriously wrong with Apple specs and support pages claiming 4K/60Hz support on rMB, where it clearly doesn't appear to work.

- Let's be fair, though. It hasn't yet been tested how it behaves in clamshell mode (because it can't be tested yet because of a lack of cables/adaptors). It's quite possible it would do 60Hz then - though I agree with you that Apple usually assumes an extended desktop with both the internal and an external display in their specifications.

 

[ctyrider]

Let's be fair, though. It hasn't yet been tested how it behaves in clamshell mode (because it can't be tested yet because of a lack of cables/adaptors). It's quite possible it would do 60Hz then

Yes, but Apple's Tech Specs page for rMB clearly states that simultaneous internal and 4K/external displays are supported (although they don't specify 60Hz on that page).

I find all this to be highly misleading.

 

[JTToft]

Yes, but Apple's Tech Specs page for rMB clearly states that simultaneous internal and 4K/external displays are supported (although they don't specify 60Hz on that page).

- Precisely.

And yes, it is confusing. But I don't think we have established it being misleading yet - none of the specifications from Apple have been proven wrong.
Ars Technica established that the MacBook Tech Spec page is correct, and we can't yet disprove the 4K support document because of a lack of cables to test clamshell mode.

 

[ctyrider]

And yes, it is confusing. But I don't think we have established it being misleading yet - none of the specifications from Apple have been proven wrong.
Ars Technica established that the MacBook Tech Spec page is correct, and we can't yet disprove the 4K support document because of a lack of cables to test clamshell mode.

LOL, OK.. you should be a lawyer for Apple.

If Apple claims 4K/60Hz support over SST using 10.10.3 - this should be working out of the box.. And without going through acrobatics, like closing the lid, which makes it impossible to even use rMB with a DisplayPort screen based on currently shipping products.

 

[JTToft]

LOL, OK.. you should be a lawyer for Apple.

If Apple claims 4K/60Hz support over SST using 10.10.3 - this should be working out of the box.. And without going through acrobatics, like closing the lid, which makes it impossible to even use rMB with a DisplayPort screen based on currently shipping products.

- Hah. I don't think they'd have me, what with the lack of a law degree and all.

I agree completely. There's a wee bit too much hoop-jumping and trapeze swinging involved here.

 

[ctyrider]

BTW.. Apple "4K Monitor Support" page also claims that 2014 MacMini supports 4K at 60Hz. No one has been able to get this to work either:

https://forums.macrumors.com/posts/20983805/

No lid to close on Mac Mini I am afraid

 

[JTToft]

BTW.. Apple "4K Monitor Support" page also claims that 2014 MacMini supports 4K at 60Hz. No one has been able to get this to work either:

https://forums.macrumors.com/posts/20983805/

No lid to close on Mac Mini I am afraid

- Well, something's not right.
It's also interesting that the support document very vaguely claims only that "most" single-stream 4K displays are supported...