Skip to main content
  1. Home
  2. Computing
  3. News

M1 Macs could have a problem with their Thunderbolt ports

David Matthews
By

Imagine paying for an expensive Mac only to discover you’re not getting full Thunderbolt 4 speeds. That’s what some M1 Mac pro users are reporting after several transfer speed tests.

Howard Oakley from Eclectic Light performed different tests with the 2021 16-inch M1 Max MacBook Pro and a 2022 Mac Studio, also with the M1 Max. He also used a range of external SSDs from both Crucial and Samsung. The tests suggests that although both Macs support Thunderbolt 4, they don’t support the USB 3.1 Gen 2 standard, hindering transfer speeds.

A side profile of the 2021 MacBook Pro.
Digital Trends

Oakley first determined what the theoretical speeds were by connecting the external SSDs to an Intel iMac Pro and verified that USB 3.1 Gen 2 was supported. For context, USB 3.1 Gen can transfer up to 10 Gb/s. He also ensured that only certified Thunderbolt 4 cables were used.

Recommended Videos

The actual tests included transferring 160 files ranging in size from 2 MB to 2 GB. As a control, the Intel iMac Pro recorded 470 MB/s read speeds and 480 MB/s write speeds. By contrast, Oakley confirmed that read speeds on M1 Macs ranged between 386 Mb/s and 406 Mb/s while write speeds were between 430-435 MB/s.

Related

Connecting to one of the two ports on the front of the Mac Studio using a Thunderbolt 4 cable produced terrible performance at 20 MB/s reads and 37 MB/s writes.

Here is a summary of the results:

  • USB 3.1 Gen 2 storage connected direct to a Thunderbolt port on an M1 Mac was limited to 5 Gb/s, giving read rates of about 400 MB/s and write rates of about 430 MB/s.
  • USB 3.1 Gen 2 storage connected to a USB-C port on the front of a Mac Studio Max using a USB-C cable, or via a USB-C port on a Studio Display, operated at 10 Gb/s, with read and write rates of about 500 Mb/s and 490 MB/s.
  • USB 3.2 storage connected directly to a Thunderbolt port on an M1 Mac operated at 10 Gb/s, with read and write rates of about 910 Mb/s and 970 MB/s.
  • USB 3.1 Gen 2 storage connected to a USB-C port on the front of a Mac Studio Max using a Thunderbolt 4 cable operated at 10 Gb/s, but read and write speeds were lowest of all, at about 20 and 40 MB/s.

At the end, Oakley offers several conclusion and recommendations, one of which is for those with USB 3.1 Gen 2 devices to use Thunderbolt 3 docks or the USB ports on the Studio Display. He also mentions that Apple should have informed people about slower transfer speeds or issued a firmware patch if the slow speeds are due to bugs.

Admittedly, with the exception of the front USB ports on the Mac Studio, the transfer speeds aren’t terrible compared to the actual USB 3.1 Gen 2 spec. However, with customers paying at least $2,000 for a base M1 Pro MacBook Pro and M1 Max Mac Studio, one would hope to get the full Thunderbolt 4 speeds.

Editors' Recommendations

Topics
David Matthews
David Matthews
Former Digital Trends Contributor
David is a freelance journalist based just outside of Washington D.C. specializing in consumer technology and gaming. He has…
The case for buying the M2 MacBook Air over the M3 model
The screen of the MacBook Air M2.

Apple's MacBook Air M2 recently stood at the top of our list of best laptops, and for good reason. It's incredibly well-built, exuding an elegance that few laptops can match. It's also plenty fast for productivity users, and its GPU is optimized for creators. Its keyboard, touchpad, and display are all top-notch.

Enter the MacBook Air M3, which (hint) took over the MacBook Air's place on that list. The upgraded chipset offers even faster performance, particularly in GPU-intensive apps, and the M3 model supports an additional external display (with the display closed). It's $100 more, but is that uptick in price justified? Let's dig in.
Specs and configurations

Read more
Why you should buy a MacBook Pro instead of a MacBook Air
The 14-inch MacBook Pro on a window sill.

There are plenty of reasons to buy a MacBook Air instead of a MacBook Pro. If you want a MacBook on a budget, you don't necessarily need the goodies that come with upgrading to the MacBook Pro.

That being said, I'm going to argue for spending a little more. In my experience, the MacBook Pro offers several distinct advantages that help justify a higher price, especially with the introduction of the more affordable MacBook Pro 14 with the base M3. If you can stretch your budget a bit, here's why I think you should buy a MacBook Pro instead of a MacBook Air.
Setting the stage: pricing

Read more
Which color MacBook should you buy? Here’s how to pick
The MacBook Air on a table in front of a window.

Apple’s MacBook laptops come in a range of colors, and selecting which is right for you can be a tricky business. Sure, it’s perhaps not as important as deciding which chip to pick or how much memory you should buy, but it’s still a vital part of the equation. After all, you’re going to see that color every time you reach for your MacBook. You don’t want it to be something that fills you with regret.

But how should you pick a MacBook color? And what do the colors even look like in the first place? We’ve got the answers to those questions in this guide. We’d also advise you to go to an Apple Store to take a look at the MacBook colors in person, as some can be hard to appreciate just by browsing Apple’s website.

Read more