You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

About Macbook Air M1 USB-C port specifications. Two ports support for thunderbolt 3 or USB4. How about one port?

I am confused what the two USB-C ports specification is.


I read the specification on the homepage, and it says the following.


”Two Thunderbolt / USB 4 ports with support for:

  • Charging
  • DisplayPort
  • Thunderbolt 3 (up to 40Gb/s)
  • USB 4 (up to 40Gb/s)
  • USB 3.1 Gen 2 (up to 10Gb/s)”


I had thought the each two ports are thunderbolt 3 before I read the specs on the homepage.


Could you let me know if anyone knows the specification of each one port?

I know that the official information does not exist.


I am Japanese and my English is bad so I will say sorry for hard reading this question.


MacBook Air 13″, macOS 14.0

Posted on Sep 30, 2023 1:51 AM

Reply
Question marked as Top-ranking reply

Posted on Sep 30, 2023 8:34 AM

Both of the ports have the same specifications.

The ports are identical. You can use Thunderbolt 3 on either or both ports; you can use USB 4 one either or both ports. Either port will support any of the following:


Also see the following from MacBook Air with M1 chip - Tech Specs - Apple

Two Thunderbolt / USB 4 ports with support for:


  • Charging
  • DisplayPort
  • Thunderbolt 3 (up to 40Gb/s)
  • USB 4 (up to 40Gb/s)
  • USB 3.1 Gen 2 (up to 10Gb/s)



10 replies
Question marked as Top-ranking reply

Sep 30, 2023 8:34 AM in response to TommyTommyChop

Both of the ports have the same specifications.

The ports are identical. You can use Thunderbolt 3 on either or both ports; you can use USB 4 one either or both ports. Either port will support any of the following:


Also see the following from MacBook Air with M1 chip - Tech Specs - Apple

Two Thunderbolt / USB 4 ports with support for:


  • Charging
  • DisplayPort
  • Thunderbolt 3 (up to 40Gb/s)
  • USB 4 (up to 40Gb/s)
  • USB 3.1 Gen 2 (up to 10Gb/s)



Oct 1, 2023 1:28 AM in response to Servant of Cats

Thank you for your useful response.


I really wanted to know the point.


The followings are my understandings;

  • Hardware external monitor is a hardware connection.
  • Sider and AirPlay is a software connection.


I have an additional question to you about Sidecar/Airplay connection by a cable, wired.

The issue of “lags” is an annoying point. Wireless connection is not good for sidecar so I connect them by a cable.

Do you know the minimum specs of a cable for using Sidecar? e.g. USB 2.0, USB 3.0, USB 3.2 or Thunderbolt3.


If it is a software connection, it should be a high speed connection like a thunderbolt 3, 40Gb/s.

However, I have many cables with different standards, not thunderbolt. If those cables can use for Sidecar, I want to use them.



Sep 30, 2023 1:30 PM in response to TommyTommyChop

USB-C is a "Swiss Army knife" type of connector. Some USB-C ports have a lot of features. Some don't.


The USB-C ports on a M1 MacBook Air are USB4 ports. That is, they support version 4 of the USB specification, whose name the USB Implementer's Forum has chosen to write without a space. The


  • Charging
  • DisplayPort
  • Thunderbolt 3 (up to 40Gb/s)
  • USB4 (up to 40Gb/s)
  • USB 3.1 Gen 2 (up to 10Gb/s)


are different modes of operation that the computer, and the accessories attached to it, can select, as needed. If you attach most monitors, they're not going to know about Thunderbolt 3, and they're going to ignore it. They'll negotiate (or the adapter will negotiate) a USB-C (DisplayPort) connection.


If you attach an external USB hard drive or SSD, it might negotiate a USB-C (USB 3.1 Gen 2) connection.


Oct 1, 2023 9:13 AM in response to TommyTommyChop

TommyTommyChop wrote:

Thank you for your response.

The below comment is easy to understand for me that what USB-C is.
”USB-C is a “Swiss Army knife” type of connector”

I could understand that the port of M1 Macbook air is a USB4 so the port is compatibility to thunderbolt 3.


Thunderbolt is an optional enhancement to a USB-C port. My understanding is that it is an extremely common enhancement on Macs. I can think of only a couple of cases where Macs don't have it:

  • 12" Retina MacBooks have USB-C ports that support (USB, DisplayPort, charging), but not Thunderbolt.
  • The front-panel USB-C ports on Mac Studios with the M1 Max and M2 Max chips support USB – but not DisplayPort or Thunderbolt. For those, you use the full-featured USB-C ports on the back.


For USB4 host ports, my understanding is that

  • Thunderbolt is optional. (Macs support it.)
  • A new USB4 "up to 40 Gbps" USB transfer mode is optional. (Macs support it. No accessories do – yet.)
  • USB 3.2 Gen 2x2 ("up to 20 Gbps") is optional. (Macs don't support it, and will fall back to "up to 10 Gbps" mode if you plug in an external USB 3.2 Gen 2x2 SSD.)


https://en.wikipedia.org/wiki/USB4


Sep 30, 2023 1:44 PM in response to TommyTommyChop


TommyTommyChop wrote:

I use one external monitor.
For me, I use my ipad for external monitor using sidecar.
This is three monitor system, macbook air display, external display and ipad display.


The "one external display" limit is for first-class, hardware-supported displays. There's hardware on the M1 chip whose job is to continuously refresh the internal display, and the one external display, without missing a beat and without putting much of the work on the main CPU.


Sidecar/iPad and AirPlay are more software-driven. The CPU has to take a more active role in packaging up video information and sending it over to the display device. So you might notice some "lags" that you don't see with the dedicated hardware monitor.


On the other hand, the Sidecar/iPad display doesn't count against the "one external display" limit. I do not believe that AirPlay does either. So you could potentially add another display by using AirPlay to an Apple TV set top box, or using AirPlay to another Mac that is recent enough to act as an AirPlay receiver.


Oct 2, 2023 4:59 AM in response to Servant of Cats

Thank you for the reference information.


I could understand UCB4 completely.

If my mac’s USB4 was a USB 3.2 Gen 2x2, it could be perfect.


For USB4 host ports, my understanding is that
Thunderbolt is optional. (Macs support it.)
• A new USB4 "up to 40 Gbps" USB transfer mode is optional. (Macs support it. No accessories do – yet.)
• USB 3.2 Gen 2x2 ("up to 20 Gbps") is optional. (Macs don't support it, and will fall back to "up to 10 Gbps" mode if you plug in an external USB 3.2 Gen 2x2 SSD.)

https://en.wikipedia.org/wiki/USB4


About Macbook Air M1 USB-C port specifications. Two ports support for thunderbolt 3 or USB4. How about one port?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.