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Reliable 25 Gigabit Ethernet via Thunderbolt
  • zokier
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  • 32 minutes ago
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Note that you can do point-to-point network links directly with thunderbolt (and usb4).

https://support.apple.com/guide/mac-help/ip-thunderbolt-conn... etc

Yes! However, I got around 15 Gbps with a Thunderbolt-only setup (TB3/TB4) = only 75% of the Ethernet setup.

You'd also mostly be limited to short cables (1-2m) and a ring topology.

Thunderbolt is basically external PCIe, so this is not so surprising. High speed NICs do consume a relatively large amount of power. I have a feeling I've seen that logo on the board before.
I don't know how to measure the direct power impact on a MacBook Pro (since it's got a battery), but the typical power consumption of these cards is 9 W, not much more than Aquantia 10 GBit cards.

Also, if you remember where you saw that logo, please let me know!

  • consp
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  • 1 minute ago
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Plus 1-2.5w per active cable. You need the heatsinks as the cx4 cards expect active airflow, and active transceivers as well.
  • xattt
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  • 48 minutes ago
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The PCI-E logo or the “octopus in a chip” logo? I’m more interested in the latter.
Neat, but the thermal design is absolutely terrible. Sticking that heatsink inside the aluminum case without any air circulation is awful.
Yeah, it's because the network card adapter's heatsink is sandwiched between two PCBs. Not great, not terrible, works for me.

The placement is mostly determined by the design of the OCP 2.0 connector. OCP 3.0 has a connector at the short edge of the card, which allows exposing/extending the heat sink directly to the outer case.

If somebody has the talent, designing a Thunderbolt 5 adapter for OCP 3.0 cards could be a worthwhile project.

A Flex PCB connecting the OCP2 connector would allow to put the converter board behind the NIC board, allowing the NIC board to be exposed to the aluminum case to use the case itself as a heatsink (would need a split case so the NIC board can be screwed to one side of the case, pressing the main chip against it via a thermal pad).

As a stop-gap, I'd see if there was any way to get airflow into the case - I'd expect even a tiny fan would do much more than those two large heatsinks stuck onto the case (since the case itself has no thermal connection to the chip heatsink).

Now I just have to contrive the circumstances where this is useful to me. :)
  • mcny
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  • 1 hour ago
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I don't know about the Ethernet part but it bothers me that even wifi has become faster than the wired USB port on our phones.

All I want to do is copy over all the photos and videos from my phone to my computer but I have to baby sit the process and think whether I want to skip or retry a failed copy. And it is so slow. USB 2.0 slow. I guess everybody has given up on the idea of saving their photos and videos over USB?

> USB 2.0 slow

Many phones indeed only support USB 2.0. For example the base iPhone 17. The Pro does support USB 3.2, however.

> I guess everybody has given up on the idea of saving their photos and videos over USB?

Correct.

Wifi is fast but the latency is terrible and the reliability is even worse. It can go up and down like a yo-yo. USB is far more predictable even if it is a bit slower.
> given up on the idea of saving their photos and videos over USB?

Until USB has monthly service fee business to compete with cloud storage revenue.

Why don't you get a phone with 3.0+ USB?

My last two phones in the last 4 years had at least USB 3.1

> but I have to baby sit the process and think whether I want to skip or retry a failed copy

Do you import originals or do you have the "most compatible" setting turned on?

I always assumed apple simply hated people that use windows/linux desktops so the occasional broken file was caused by the driver being sort-of working and if people complain, well, they can fuck off and pay for icloud or a mac. After upgrading to 15 pro which has 10 gbps usb-c it still took forever to import photos and the occasional broken photos kept happening, and after some research it turns out that the speed was limited by the phone converting the .heic originals into .jpg when transferring to a desktop. Not only does it limit the speed, it also degrades the quality of the photos and deletes a bunch of metadata.

After changing the setting to export original files the transfer is much faster and I haven’t had a single broken file / video. The files are also higher quality and lower filesize, although .heic is fairly computationally-demanding.

Idk about Android but I suspect it might have a similar behavior

rsync...grsync...a solution for broken partial batch transfers since forever
Wouldn’t this be useful for clustering Macs over TB5? Wasn’t the maximum bandwidth over USB-cables 5Gbps? With a switch, you could cluster more than just 4 Mac Studios and have a couple terabytes for very large models to work with.
I was hoping somebody would suggest that (and eventually try it out).

With TB5, and deep pockets, you might probably also benchmark it against a setup with dedicated TB5 enclosures (e.g., Mercury Helios 5S).

TB5 has PCIe 4.0 x4 instead of PCIe 3.0 x4 -- that should give you 50 GbE half-duplex instead of 25 GbE. You would need a different network card though (ConnectX-5, for example).

Pragmatically though, you could also aggregate (bond) multiple 25 GbE network card ports (with Mac Studio, you have up to 6 Thunderbolt buses, so more than enough to saturate a 100GbE connection).

Remote Time Machine backups are snappier than ever before :)
  • e40
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  • 1 hour ago
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Porn?
What kind of porn requires 25 gigabits ?
A lot of porn.