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macrumors bot
Original poster
Apr 12, 2001

The licensing group behind the HDMI interface has introduced a new HDMI Alternate Mode that will allow for USB-C devices like the 12-inch MacBook, smartphones, and tablets to connect to HDMI-enabled 4K displays and TVs over a single cable, with no adapters or dongles required.


The new specification will lead to the release of simple HDMI to USB-C cables that support the full range of HDMI 1.4b features, including 3D, Ethernet, and CEC. Connecting an HDMI-enabled 4K display or TV to a 12-inch MacBook currently requires using Apple's $79 USB-C Digital AV Multiport Adapter.


Thunderbolt remains the more popular I/O protocol for connecting 4K displays and TVs to Macs, since existing models are unable to drive 4K displays or TVs at 60Hz over HDMI by default. HDMI-enabled 4K displays and TVs connected to a 12-inch MacBook via adapter, for example, only support a 30Hz refresh rate.

In addition to the 12-inch MacBook, Apple is rumored to release updated MacBook Pro and MacBook Air models featuring USB-C ports with Thunderbolt 3 as early as October. Those notebooks would support HDMI to USB-C cables, providing Mac users with another option for connecting 4K displays and TVs.

Article Link: HDMI Announces USB-C to HDMI Cables for 4K Displays and TVs
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macrumors regular
Aug 26, 2016
Alt-Mode is certainly a nice option and a step in the right direction, but no HDR and not being able to draw power is a bit of a bummer. You'll still need an adapter if you want to do work with your MacBook.


macrumors 65816
Aug 16, 2013
30hz is fine for people to do their presentations with - no one should be using HDMI out to connect an actual monitor for work.
That’s only true if you’re using a 4K monitor for work because the 30Hz refresh rate only applies to 4K screens. If you’re using either a 1080p monitor, or maybe even a 2K monitor, you should be able to get 60 Hz.
[doublepost=1472738597][/doublepost]I wonder if this adapter would work on an Ubuntu Phone. I’m curious because all four Ubuntu phones have USB-C and lack HDMI.


Staff member
Feb 1, 2005
Twin Cities Minnesota
Hopefully it actually allows the HDCP to pass through so we can actually use things like Netflix and other services with that need. It's one thing to be in the specification, it's another for it to actually work.
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