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macrumors 68000
Original poster
Oct 6, 2020
To continue with the disk-based threads about USB speeds & external enclosures, can anyone hazard a guess whether the commonly-observed poor USB speed on M1 Macs can be fixed in software?

I find it disappointing that Apple has released a series of new machines that have significantly worse performnace in a key metric such as USB transfer speed.

I have now tested at least 5 external disks (both SSD and HDD) and consistently measured slower transfer speeds on my M1 Mini compared to my Intel MBP16.

This is independent of the problem that causes some USB 3.1 gen2 (or 3.2 gen2) devices to connect at only 5Gbps instead of 10Gbps.

I just bought 2 SSDs and thought I would test them out.

The first is a 500GB Samsung 860 Evo (2.5" format). On the M1 I get 300/330MBps (read/write), on the MBP16 I get 425/430MB/s.

The second is a 1TB Samsung T7. On the M1 Mini I get 667/723 (read/write), on the MBP16 I get 870/830ps (read/write).

This is a bit disappointing!

Is it the USB controller hardware (presumably part of the SoC)? Or the software implementation?

Even on the same M1 Mini, there is a difference between the USB-A ports and the USB-C ports when connecting at 5Gbps, with the USB-C/TB3 ports being about 20-50MBps faster. Via the USB-A ports, I have one SATA3 SSD (capable of c. 420MBps read/write on an Intel Mac) that only gets around 280MBps...not much better than a Seagate 8TB HDD I have that reads & writes at over 200MBps.

Apple dropped the ball with this one....


macrumors 6502a
Oct 31, 2018
Toronto, Canada
Unfortunately, I don’t think anyone knows the answer to this question for sure.

I see similar results with my M1 Air and M1 mini.

My assumption is that this is probably firmware related, and is improvable (to a point), but whether Apple attempts to improve it or not is another question entirely. But, I would hope so.


macrumors Core
Oct 14, 2008
Since we don’t know what is the source of these problems, I’d go with an uninformed prior and say 50/50 :)

It is also quite interesting that Apple got so many complicated things right (CPU, GPU, power efficiency) and yet they have problems with seemingly everyday things like USB, displays and Bluetooth. Third party compatibility is really tricky. I can imagine that there are miriads niche cases that have to be taken care of, and this is a totally new field for Apple. They will get it right eventually, and let’s hope that these things can be fixed in software for the existing systems.


macrumors Penryn
Feb 20, 2009
My totally uneducated guess:
This could be a problem with both hardware and software.
As such, it cannot be "fixed" on the current lineup of m1 Mac products.

It -might- get fixed with later versions of the m-series CPU (such as the new iMacs coming around the time of WWDC)...


macrumors 6502a
Sep 22, 2009
United States
I'm starting to become skeptical that Apple will be able to solve some of these issues through software. Keeping my fingers crossed, but I have a feeling early-adopters may be screwed and that a number of these issues will only be fixed in later hardware revisions. (If these were just software bugs, I would think many of them would already be resolved, as they are pretty serious issues.)
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