MAC Mini M4 Ethernet capped using docking station

[DJdan1973]

I just purchased an OWC Thunderbolt 5 docking station. When I plug the RJ45 cat6 cable into the Ethernet port on the docking station I only get 1g down speed. If I use my 2.5g adapter (plugged into docking station) I get 1800gig down. What is causing the Ethernet port on the docking station to cap out at 1g? Initially I bought a uGreen docking station and the same thing occurred. I returned the uGreen docking station thinking it was defective. It appears the MAC Mini M4 sees an Ethernet port and mirrors it to what the MAC Mini M4 Ethernet port is. Thoughts on how to fix this, or am I stuck using the 2.5g adaptor to get the speed I pay for?

 

[IvyKing]

What does the spec sheet for the OWC Thunderbolt 5 docking station say about the Ethernet port? Sounds like the port might be just a 1G.

 

[DJdan1973]

What does the spec sheet for the OWC Thunderbolt 5 docking station say about the Ethernet port? Sounds like the port might be just a 1G.

The port is 2.5Gb Ethernet. https://www.owc.com/solutions/thunderbolt-5-dock

 

[FreakinEurekan]

I suppose it’s possible someone here on MacRumors has the same dock and 2.5G Ethernet and will provide some guidance. But, my first contact would be OWC, not MacRumors.

 

[PaulD-UK]

OWC’s page says “Whether you’re using the latest Thunderbolt 5 system, an older Thunderbolt 3 Mac, or a USB-C device, this dock adapts…”

So if you connect it to a TB4 Mac, not to a TB5 Mac, quite likely that’s how it ‘adapts’…
It could be sharing the Ethernet port bandwidth with the USB ports?

TB4 restricts all the dock’s non-TB ports to a total of 10Gbps, whereas TB5 has more bandwidth to share with less restrictions.

 

[DJdan1973]

I suppose it’s possible someone here on MacRumors has the same dock and 2.5G Ethernet and will provide some guidance. But, my first contact would be OWC, not MacRumors.

I contacted OWC. still waiting for their reply.

I suppose it’s possible someone here on MacRumors has the same dock and 2.5G Ethernet and will provide some guidance. But, my first contact would be OWC, not MacRumors.

 

[DJdan1973]

I suppose it’s possible someone here on MacRumors has the same dock and 2.5G Ethernet and will provide some guidance. But, my first contact would be OWC, not MacRumorI contcated

It's just odd that a 2.5g adapter works fine plugged into a USB-C port on the TB5 dock. I think it has something to do with the MAC Mini, since the uGreen dock with 2.5g Ether did the same thing. I even reimaged the MAC Mini and the issue still occurred.

OWC’s page says “Whether you’re using the latest Thunderbolt 5 system, an older Thunderbolt 3 Mac, or a USB-C device, this dock adapts…”

So if you connect it to a TB4 Mac, quite likely that’s how it ‘adapts’…
It could be sharing the Ethernet port bandwidth with the USB ports?

TB4 restricts all the dock’s non-TB ports to a total of 10Gbps, whereas TB5 has no restriction.

 

[IvyKing]

OWC’s page says “Whether you’re using the latest Thunderbolt 5 system, an older Thunderbolt 3 Mac, or a USB-C device, this dock adapts…”

So if you connect it to a TB4 Mac, quite likely that’s how it ‘adapts’…
It could be sharing the Ethernet port bandwidth with the USB ports?

Since the OP stated that an adapter plugged into the Docking station supported 2.5G, I don't the the Thunderbolt connection is the problem.

One possibility is that whatever is on the other end of the Cat6 cable is a marginal 2.5G port and with the circuitry in the docking station being in close proximity to the Ethernet PHY, the docking station PHY can't get a high enough signal to noise ratio (SNR) to support 2.5G. An external adapter has its PHY in a quieter environment and thus gets a sufficiently good SNR to make a 2.5G connection.

1G and faster Ethernet PHY's are effectively modems with all sorts of signal processing issues. I spent a week or so trying to figure out why boards with a 1G Ethernet wouldn't work at 1G, but worked fine at 100M and 10M. One of the boards did work at 1G as long as the PHY was kept cool - turns out the problem with boards was the bias setting resistor was the wrong value.

 

[Fishrrman]

It would help if we knew what "PHY" is...?

I recall reading that with some external 2.5 adapters, there can be controller chip/driver problems (Realtek chips come to mind here).

I don't have a tbolt dock, or 2.5gb ethernet. But I was investigating tbolt4 docks for my m4 Mini, and in the process of reading amazon reviews for the amazon basics dock, some reviewers mentioned problems getting 2.5gb from the ethernet port on those. And again, the issue of "drivers" came up.

OP:
When you receive a response from OWC, let us know what they say.

In the meantime, perhaps this would apply:
Fishrrman's "Mac Rule Number 2":
Use what works for you. Don't waste your time trying to use what doesn't.

 

[DJdan1973]

It would help if we knew what "PHY" is...?

I recall reading that with some external 2.5 adapters, there can be controller chip/driver problems (Realtek chips come to mind here).

I don't have a tbolt dock, or 2.5gb ethernet. But I was investigating tbolt4 docks for my m4 Mini, and in the process of reading amazon reviews for the amazon basics dock, some reviewers mentioned problems getting 2.5gb from the ethernet port on those. And again, the issue of "drivers" came up.

OP:
When you receive a response from OWC, let us know what they say.

In the meantime, perhaps this would apply:
Fishrrman's "Mac Rule Number 2":
Use what works for you. Don't waste your time trying to use what doesn't.

Thanks! I'll post back when OWC responds. The only drivers for MAC on OWC's website is the Dock Ejector (not sure who would need that). Strange is they don't have TB5 dock drivers.

 

[IvyKing]

The "PHY" is the "controller chip" that converts the binary logic level (0V, ~1V for today's CPU's) data stream to/from the signal levels used in Ethernet cabling. For 10BaseT and 100BaseT, each 8 bit byte was encoded into a 10 bit signal to allow AC coupling through transformers. One twisted pair of the four pair cable was used for transmitting in one direction and another was used transmitting in the other direction. That's why special cables were needed to attach two computers directly. For 1000BaseT and above, the data stream was used to phase/amplitude modulate carriers on each of the for twisted pairs, with simultaneous transmission in both directions just as a dial-up modem could simultaneously send and recieve on a single phone line.

The point is that the signals are analog in nature and noise or distortion can limit the maximum speed for data transfer, just as line noise or other problems on a phone line could limit speed on a dial up connection. When I got my first 56K modem, it almost always took a couple of trys to connect and never got much above 30K. I bought a longer phone cable so I could still get online with the computer much further away from the phone jack in the wall - was really surprised when it established connection almost immediately with the 53K rate.

 

[tonmischa]

If I use my 2.5ghz adapter (plugged into docking station) I get 1800gig down. What is causing the Ethernet port on the docking station to cap out at 1gig?

I am with @IvyKing here. You could have some analog issues. (Which could also explain why 2 docks from different manufacturers did not work as expected. also why the 2.5Gb (you wrote ghz, but you meant GigaBit, right?) adapter gets only 1.8Gb instead of the expected 2.5Gb...)
Stupid question: Did you try a different ethernet cable? Is is CAT6? How long? Damaged/Bent in any way? What network switch do you have? Many cables connected to / lying on / lying around that switch?

 

[Anonymous Freak]

I would find it odd that OWC would use an Ethernet chip that doesn't have proper macOS drivers, considering their Mac focus; but that's what it seems like.

I have a USB 5GbE adapter that in macOS only works at 1Gb speed, but in Windows, it supports full 5Gb. Even on Mac hardware (older Intel MacBook Pro.) But a different USB 5GbE adapter works at full 5Gb just fine on macOS. Both are "generic" no-name adapters, but they use different chips inside. One chip obviously has full macOS support, the other doesn't.

Last thing to check - I assume you're doing some sort of network speed test, but does your router/hub have lights that change color based on the connection speed? If so, what does it show for the two different Ethernet ports? And if you go in to System Settings -> Network -> the Ethernet adapter -> Details -> Hardware, what does it show for the connection speed? This will show you the actual Ethernet connection speed, not just a speed test result.

(Screenshot from this page on my Mac Studio, showing a "10Gbase-T" connection, 10 Gigabit.)

If that shows the full 2.5Gbase-T, but you're only speed testing 1 Gb/s, then there's another bottleneck somewhere. Perhaps OWC has the ethernet chip bandwidth-constrained internally, but because your external USB Ethernet dongle is connecting to a Thunderbolt port, it gets full Thunderbolt bandwidth. In which case I'd ask what other devices you have plugged in to the dock.

 

[Fishrrman]

Anonymous wrote:
"I have a USB 5GbE adapter that in macOS only works at 1Gb speed, but in Windows, it supports full 5Gb. Even on Mac hardware (older Intel MacBook Pro.) But a different USB 5GbE adapter works at full 5Gb just fine on macOS. Both are "generic" no-name adapters, but they use different chips inside. One chip obviously has full macOS support, the other doesn't."

Thanks for the info.
Do you have any way of telling which chips "the good one" has?
(and also "the bad one")...?