A Note About USB Performance on M1 Macs

Apple silicon has revolutionized personal computing. From the line's inception in 2010 with the release of the A4 processor in the iPhone 4 and the original iPad, its combination of speed and low power consumption remain unmatched today.

The iPhone continues to enjoy a healthy performance gap over its competition while the Mac platform—now almost entirely powered by Apple M-Series processors built from the foundation the A-Series established—is redefining what creative professionals can accomplish on the go with ARM-based hardware.

And while the transition from Intel processors to M-Series processors on the Mac has been nothing short of impressive, it is still a platform in its nascent years and there are bound to be hiccups and growing pains. Case in point is a performance issue the team here at OWC recently discovered in Macs with M-Series chips.

The issue itself is related to decreased performance of seemingly all USB-connected peripherals, regardless of brand or type. However, the severity of the issue depends on whether you have a base M1 processor in your Mac or an M1 Pro, M1 Max, M1 Ultra, M2, M2 Pro, or M2 Max.

If you have a base configuration M1, keep reading. If you have any other M-Series chip, just know that you should update to macOS 13.3, released March 27, 2023. Prior releases contained a bug that caused decreased USB performance on other M-Series chips, but upgrading to macOS 13.3 should fix the issue for you.

If you have a base M1 machine, however, you'll still see lower USB performance even after updating to macOS 13.3. Specifically, we’ve seen write speeds on NVMe drives up to 44% lower on base M1 configuration Macs than what they are on Macs with other M-Series processors or an Intel chip. That’s really the basis for this whole post, unfortunately.

We tested two external NVMe SSD drives and an OWC Mercury Elite Pro Dual with 3-port hub and two 2.0TB Mercury Extreme Pro 6G SSDs inside, connected to the following Macs, all running macOS 13.3:

• MacBook Air 10,1 with an M1 processor
• MacBook Pro 18,2 with an M1 Max
• Mac Mini 14,2 with an M2
• Mac Mini 14,10 with M2 Pro
• MacBook Pro 15,2 with an Intel processor

We tested each drive connected directly to each machine and connected through a dock. As you can see, the most dramatic decline in performance is seen in write speeds on the M1 MacBook Air.