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Is the USB speed issue fixed with the M2 ?
- Thread starter DrCC
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USB3.2 is not 20gbps, it is also 10gbps the same as USB3.1, except there is an additional "gen 2x2" mode that supports 20gbps, but there's basically no device that actually supports 2x2. Without explicitly claiming 2x2, a USB 3.2 device only supports 10gbps that's just the way it's supposed to be.
The ports are supposed to be USB4 which does not entail it will supports all the other random nonsense in the USB standard.
The ports are supposed to be USB4 which does not entail it will supports all the other random nonsense in the USB standard.
It's ridiculous how convoluted the USB 3.x naming schemes managed to become. Especially given that the majority of USB 3.x devices only implement 5gps standards, and many ports don't even support the faster ones.
I'm glad USB4 is at least trying to fix some of that nonsense. It's still a mess because of USB-C cable confusion, but at least the naming schemes themselves are getting better.
I thought the problem is that M1 machines do not consistently support 10gbps?
That was certainly true of the M1s but I haven't heard if it holds for the M2. Anyone done any testing? I've also heard that there is pretty good evidence that it is a software issue but I don't remember the details.
M1 is not just slower with 10Gb/s drives but also with 5Gb/s by roughly the same percentage.
M2 seems to have a similar issue too from the reviews I have seen online
M2 seems to have a similar issue too from the reviews I have seen online
Any links? There was so much click bait I stopped watching and reading reviews.
I have gen 2x2 device and a PCIe card but macOS doesn't seem to support gen 2x2. I also checked Ventura.
There's multiple problems. The latest problem found is that the front USB ports of Mac Studio with M1 Max are limited to 8 Gbps because Apple gave the ASM3142 only one gen 3 PCIe lane.
Read this thread: USB on M1 Macs isn't actually 10Gb/s? (Also definitely not USB4)
I’m up to date on that thread and as far as I know, no one has posted anything related to the M2 yet.
Any link to M2 speeds? I have seen tests online but haven't kept track of it so cannot link. As for 5Gbs being slower too, that's my own tests (so it's not slower just at 10Gbps, it's 25% slower regardless)
Not really. I find them closer to Intel speeds, at least for my SD Extreme v2 when I tested it before encrypting the drive.
When talking about M1 and M2, do you mean only M1 and M2 or M1 series (M1, M1 Pro, M1 Max) and M2 series (M2, M2 Pro, M2 Max)? I wonder if there are differences because M1 and M2 alone only support one display while those with a Pro and Max at the end support at least two displays.
Again, M1 Pro and probably Max reaches within 5-10% of the Intel chips which isn't terrible like the regular M1.
you'll probably have to move to TB drives if speed is important for you since Apple hasn't fixed this so far (if it's even fixable).
So is this a firmware issue or hardware limitation of the M1? All their website information still advertises 10Gb/s specifically.
I didn't do any benchmarking but a Samsung T5 that connects at 10Gbps on an Intel Mac still only connects at 5Gbps on an M2 Air.
10 Gbps is the signal speed. The data speed (after PCIe and USB protocol overhead) is between 5Gbps and 8.5 Gbps.
My Intel Mac mini 2018 can do 8.5 Gbps of data (1060 MB/s) with AmorphousDiskMark.app. M-series Macs are less than that.
USB devices that connect at 5 Gbps instead of 10 Gbps is another problem. In that case you need to connect them to a hub to get a 10 Gbps connection.
However, sometimes a USB controller (such as the ASM1142) lies about the connection speed. It may report 5 Gbps connection in System Profiler.app but is actually connected at 10 Gbps and can do ≈6.4 Gbps of data (since ASM1142 is limited by 8 Gbps PCIe).
T5 is only rated at 5 Gbps, not 10. Doesn't matter what the system reports it as. The SSD inside is m. sata and not NVMe.
So on an M1 iMac with four ports, should I use the two USB3 ports over the two TB4/USB4 ports, because of less protocol overhead?
USB controllers use the same protocols. The difference in performance between the USB controller of USB M-Series Thunderbolt ports and other USB controllers is maybe caused by something outside the USB protocol, such as drivers or hardware...
...Unless one is using UASP and the other isn't? Check the ioreg to see what driver the connected USB mass storage device uses. For Intel Macs: IOUSBMassStorageUASDriver for UASP, IOUSBMassStorageDriver otherwise. I don't know if M-Series Macs use the same USB mass storage drivers as Intel. I don't know if UASP improves performance much over non-UASP.
Need to examine the ioreg to see if the USB controller for the USB only ports of the iMac is connected with 2 lanes of PCIe gen 3 to make sure it's not limited like the USB controller of the Mac Studio that has front USB (non-Thunderbolt) ports.
https://forums.macrumors.com/threads/issues-with-usb-ports-on-m1-max.2355896/post-31367729