Mac mini M1 USB-C power limitation

[John Malkovich]

Long-time lurker, first-time poster here.

I am trying to solve the problem of power limitation on Mac mini M1 USB-C port, which makes my external SSD disconnect under load.

I use external NVMe SSD (XPG, 1TB) in LC Power USB 3.2 Gen2 enclosure and I am able to achieve decent speeds. No disconnects or ejects occur until symultaneous read/write tasks, when the notification "disk ejected" appears and the disk immediately reconnects. This also happens on CCC backup tasks. Just for the record, I was able to replicate this many times, so the problem is not a loose connection or cable.

Looking at System Report, the power requirement of the disk is steadily at 896mA out of 900mA available on port. Apparently, the SSD power draw at times becomes excessive, causing it to shut down and immediately remount.

I was looking for NVMe enclosures with external power supply, but I haven't found any.

I am considering Samsung X5 and would appreciate if a Mac mini M1 owner using Samsung X5 as external disk can confirm that no spontaneous eject occur under load. Alternatively, could you suggest other enclosures, even TB3, which are not power-hungry?

Thank you in advance for your advice.

 

[MBAir2010]

would appreciate if a Mac mini M1 owner using Samsung X5 as external disk can confirm that no spontaneous eject occur under load. Alternatively, could you suggest other enclosures, even TB3, which are not power-hungry?

Thank you in advance for your advice.

I have the same MacMini M1 that reads 3 OWC Mac sales enclosures with 2 their ssd drive and a WD ssd drive
connected to a Satechi 4-slot usbC dock, the travel one.
the write speeds are fast I just never measure them in "geek tech numbers" but I can copy paste a 5GB in seconds flat.
these M1 chips are rally great and fast!

as far as using the brand you described,
samsung and I are not friends anymore

hoped this helped in someway.

 

[John Malkovich]

Thank you for your reply. Speed is certainly not a concern here. Are your disks externally powered?

 

[Fishrrman]

Mr. Malkovich --

Have you considered a powered USBc hub?
Be sure that it will support USB3.1 gen2 speeds (10gb).

Although...
... I'm thinking that even with a USBc hub, there will be "overhead" that "eats up" some of the bandwidth between the Mac and the hub.

A THUNDERBOLT hub might overcome this, but they're more expensive.

You also wrote:
"Looking at System Report, the power requirement of the disk is steadily at 896mA out of 900mA available on port."

Hmmm...
Got me curious, so I plugged in a Samsung 1tb t7 Shield drive and checked System Info.
Got this:

Notice that the drive also shows exactly 896mA.
Why would they be so close?
I'm thinking that there's something "bogus" about that reading... but I can't say just what.

 

[John Malkovich]

Yes, many readings and stats in macOS are just wrong.
I am aiming at TB3 enclosure. As said, I was looking for a powered enclosure as you suggested, but the only one I have found is a multi-form factor toaster type from Orico.
But I might also give a USB 4.0 enclosure a try, for less money. It seems that M1 assigns power on USB-C port depending on connection type, and that for USB 4.0 it would be much more than the mentioned 900mA. Will report back.

 

[polyphenol]

Long-time lurker, first-time poster here.

I am trying to solve the problem of power limitation on Mac mini M1 USB-C port, which makes my external SSD disconnect under load.

I use external NVMe SSD (XPG, 1TB) in LC Power USB 3.2 Gen2 enclosure and I am able to achieve decent speeds. No disconnects or ejects occur until symultaneous read/write tasks, when the notification "disk ejected" appears and the disk immediately reconnects. This also happens on CCC backup tasks. Just for the record, I was able to replicate this many times, so the problem is not a loose connection or cable.

Looking at System Report, the power requirement of the disk is steadily at 896mA out of 900mA available on port. Apparently, the SSD power draw at times becomes excessive, causing it to shut down and immediately remount.

I was looking for NVMe enclosures with external power supply, but I haven't found any.

I am considering Samsung X5 and would appreciate if a Mac mini M1 owner using Samsung X5 as external disk can confirm that no spontaneous eject occur under load. Alternatively, could you suggest other enclosures, even TB3, which are not power-hungry?

Thank you in advance for your advice.

I have four external drives attached to my M1 mini. One spinning drive, two Samsung drives (T5 and T7) and a 128GB in an anonymous USB-C enclosure.

My usage is the spinner and the T7 for Time Machine, the T5 for extra storage, and the 128, well, just in case...

(Also other USB devices such as Watch charger, keyboard charging, memory cards, thumb drives, etc.)

Connected using USB-C to four-port mini-hubs with a combination of USB-A and USB-C sockets.

I was getting regular disconnects. Somehow they were fine when using the machine but on coming back, I'd find one or more had disconnected. But they reconnected without any apparent issues. One day, having had enough, I moved them round and change the distribution across the mini hubs and whether they use USB-A or USB-C. And they have not disconnected since.

However, I want more certainty, reliability and flexibility so have just bought a powered USB-C hub.

Aceele USB C Hub 3.2 Gen 2, 10Gbps USB C to USB C Adaptor with 4 Type-C Data Ports, 2ft USB Extension Cable Extender Splitter with Type-C Power Port for Laptop, MacBook Pro, Samsung Chromebook, Etc

Aceele USB C Hub 3.2 Gen 2, 10Gbps USB C to USB C Adaptor with 4 Type-C Data Ports, 2ft USB Extension Cable Extender Splitter with Type-C Power Port for Laptop, MacBook Pro, Samsung Chromebook, Etc

【4 in 1 USB C HUB & Type C Powered Port】Aceele USB 3.2 Hub has 4 USB 3.2 ports, backward compatible with USB 3.1/3.0. All 4 ports share 10Gbps transmission speed. hub can also work normally without Type C Powered Port connected. As an auxiliary port,connect to the hub to ensure that the hub can w...

www.amazon.co.uk

Haven't set it up yet! It only arrived this morning. And I actually can't remember exactly what is currently plugged into which existing hubs and ports on the mini.

 

[FreakinEurekan]

I'm using a Sabrent Thunderbolt 3 enclosure for my 4TB NVMe... not sure where I'd see current usage (or if it's possible with TB3) but I've never had a disconnect, been running this 24/7 since Thanksgiving.

 

[John Malkovich]

I bought Orico M2v01-c4-gy USB4 40Gb enclosure (https://www.orico.cc/us/product/detail/7328.html). I inserted XPG (Adata) M.2 1TB disk rated at 3000MB/3500MB. Black Magic Speed Test shows that this combo only reaches 1400MB/1800MB, which is double the speed of the same M.2 disk in previous USB 3.2 enclosure, however still far below the declared speeds of both the disk and the enclosure. It is also slower from what people with this 40Gbit enclosure were able to reach with M1 hardware. Enclosure only gets warm, speed tests are consistent. In System Report, the enclosure identifies as USB 4 and 40Gbps connection. I assume there is a sort of mismatch between the disk and enclosure controllers, which prevents higher speeds. Any other disk to suggest with Orico enclosure?

 

[Fishrrman]

OP:

Re reply 8 above...
Did the Orico enclosure come with a cable?
I've read where USB4 requires a special high-speed cable to achieve full speeds (and cable length may also matter).

Other than that, I'd suspect the Adata nvme SSD.
Or perhaps some kind of "conflict/mismatch" between the drive and enclosure.

 

[John Malkovich]

Yes, the enclosure came with the original cable and the same 40Gbps mark on it as the enclosure itself.
I guess I have to find a matching disk for the Intel/Jmicron controller in the enclosure.

 

[John Malkovich]

Correction: in System Report, the device reports as USB 4.0 SSD but in TB3 mode. Assuming that the practical speed of TB3 is 22Gbps, the performance is still low. The Intel JHL7440 TB3 controller supports PCIe 3.0, and the disk is also PCIe 3 Gen.

 

[Fishrrman]

I'm wondering if it could be the cable.

An information source:

USB4: The Complete Guide [2022] | Cable Matters Blog

USB4 is here, ushering in a new era of connectivity. Check out the benefits of USB4 for peripherals and cables of the future.

www.cablematters.com

 

[PaulD-UK]

Using an unbranded USB-C cable (maybe with no ID chip in it) does indeed slow down the transfer rate of transfer to my externally powered JHL7440 WD D50 dock with a SN750 2TB NVMe SSD in it. 2600 write/2800 read with a TB3 cable, but sometimes less than half that with a generic USB-C cable.

However there seem to be low write speed problems with Adata NVMes with Macs reported by manufacturers of NVMe TB3 enclosures.

 

[John Malkovich]

Turns out it was indeed the disk (or the incompatibility thereof). With Samsung 980 Pro 1TB I was able to get the speeds close to Mac mini's internal SSD. As a matter of fact, there is a list of recommended and not recommended disks by Orico (I can't find the link anymore) but Adata was certainly blacklisted.