Can the 2013 13" Macbook Air drive an external 4k monitor?

Dell has announced that they're going to release a 4k monitor under $1000 in the beginning of 2014, and also has a 24" 4k monitor around $1300. The product page for the 24" one mentions:

Optimal resolution:
3840 x 2160¹ at 60 Hz (DP1.2*)
3840 x 2160¹ at 30 Hz HDMI

The superscript 1 displays this warning:

Important Details
In order to display the 3840 x 2160 native resolution, please ensure the graphic card and its drivers used on the PC/Laptop is capable of supporting resolutions up to 3840 x 2160 at 60Hz via DisplayPort connectivity.

So the question is: Can the video card and Thunderbolt ports on a 2013 Macbook Air 13" support resolutions up to 3840 x 2160 at 60Hz via DisplayPort connectivity?

The EveryMac page for this model says it may be able to drive two daisy-chained 2560x1600 Thunderbolt monitors, and this ars report claims that two TB monitors was possible on the 2012 models. So, I'm hopeful that the laptop should be able to drive that many pixels, but I'm not sure whether the Thunderbolt ports, in mini-DP mode, speak the DP1.2 standard necessary to drive this monitor at 60Hz.

Solution 1:

No, it won't support it. The Thunderbolt 1 controller in the Air only supports DisplayPort 1.1 and you need DisplayPort 1.2 to get 4K support, as you mention in your question.

Check out http://www.anandtech.com/show/7049/intel-thunderbolt-2-everything-you-need-to-know and http://en.wikipedia.org/wiki/Thunderbolt_(interface)#Thunderbolt_2

Solution 2:

No. Thunderbolt 2 is required.

What is Thunderbolt 2?

Thunderbolt 2 is an update to the original Thunderbolt specification and takes the original’s two 10 Gbps bi-directional channels and combines them into a single 20 Gbps bi-directional channel. The amount of data able to go through a Thunderbolt connection hasn’t increased, but the throughput of a single channel has been doubled.

What does Thunderbolt 2 have to do with 4K video?

4K video (a video format that has four times the resolution as 1080p and is gaining popularity with video professionals) requires more bandwidth than the original Thunderbolt can accommodate. Thunderbolt 2 will be able to stream that 4K video and write it to disk at the same time.

Excerpt from this MacWorld Article

Solution 3:

It might be able to.

According to http://www.anandtech.com/show/7007/intels-haswell-an-htpc-perspective:

Haswell does have 4K display support and we will have a dedicated section to see how well it works.

The whole section that they're talking about:

http://www.anandtech.com/show/7007/intels-haswell-an-htpc-perspective/7

A quote:

The good news is that Haswell's 4K over HDMI works well, in a limited sort of way.

So, maybe it will, maybe it won't, since mid-2013 and early-2014 MacBook Air only has mini-DisplayPort, so, you're adding the uncertainty of a rubbish adapter into the already fragile mix.

It would be nice if someone actually tries it extensively, and reports with some more certain results.

UPDATE 0:

According to http://www.redsharknews.com/technology/item/1646-editor-hacks-2011-macbook-air-to-output-4k from 2014-04, it looks like even 2011 MacBook Air may be able to support 4K resolution, albeit only at 25Hz and with some reliability issues, and 2011 had HD Graphics 3000, as per http://en.wikipedia.org/wiki/MacBook_Air#Specifications, whereas mid-2013 and early-2014 have HD Graphics 5000 from a Haswell CPU.

UPDATE 1:

Additionally, there is a report of a 2012 MacBook Air, which has merely HD Graphics 4000, supporting a 4K Seiki -- http://forums.macrumors.com/showthread.php?t=1681560. So, I'd say chances are very good that a mid-2013 MacBook Air wouldn't have much problems with 3840x2160@30Hz, either.