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Re:New 10 GbE USB adapters are cooler, smaller, cheaper by adrian_b on Saturday April 25, 2026 @09:05AM (#47901248)
Unfortunately "USB 3.2" is just a version of the standard, which does not give any information about the performance of a USB port or device.

USB 5 Gb/s = USB 3.2 gen 1, available on Type A or Type C connectors (or on devices on a special extended micro B connector)

USB 10 Gb/s = USB 3.2 gen 2, available on Type A or Type C connectors

USB 20 Gb/s = USB 3.2 gen 2x2, available only on Type C connectors

Moreover, "5 Gb/s" is a marketing lie. The so-called USB of 5 Gb/s has a speed of 4 Gb/s (the same as PCIe 2.0). On the other hand, 10 Gb/s and 20 Gb/s, have the claimed speeds, so USB of 10 Gb/s is 2.5 times faster than USB of 5 Gb/s, not 2 times faster.

10 Gb/s USB and Ethernet have truly the same speed, but the USB overhead is somewhat higher, leading to a somewhat lower speed. However, the speed shown in TFA, not much higher than 7 Gb/s seems too low, and it may be caused by the Windows drivers. It is possible that on other operating systems, e.g. Linux, one can get a higher transfer speed.

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by mbreese on Saturday April 25, 2026 @09:45AM (#47901540)
The fact that you had to list all of the versions and speeds at the top of your post is illustrative of what the parent was trying to say. We can all look up what speed is associated with what version, but it’s not exactly a consumer friendly experience.
Re:New 10 GbE USB adapters are cooler, smaller, cheaper by adrian_b on Saturday April 25, 2026 @10:10AM (#47901686)
A few computer manufacturers do the right thing and they mark the speed on the USB ports, removing ambiguities, for example ASUS does this on my NUCs and motherboards.

Unfortunately, there are too many who do not do this, even among the biggest computer vendors.

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by riobard on Saturday April 25, 2026 @10:32AM (#47901821)
> mark the speed on the USB ports, removing ambiguities

Unfortunately it's not true.

Quiz: what happens when a device capable of 20Gbps is plugged into a port marked as 40Gbps?

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by ziml77 on Saturday April 25, 2026 @10:44AM (#47901900)
I can't tell if this is a trick question that has something to do with a quirk of USB running multiple lanes in parallel to get higher speeds.

Because if not then it's the same as any specification for connecting devices that allows for multiple speeds. It runs at the lowest of the max speeds supported of everything in the chain.

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by riobard on Saturday April 25, 2026 @11:07AM (#47902062)
That's exactly the issue. I'm just pointing out that it's a fantasy to hope for simple numbering of max supported speeds will simplify the current USB mess.

It will not.

Consumers would expect plugging a 20Gbps device into a 40Gbps port should result in 20Gbps negotiated speed. In reality it will mostly likely end up at 10Gbps (or less) because of the mess.

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by adrian_b on Saturday April 25, 2026 @12:00PM (#47902425)
Older Thunderbolt devices were not compatible with USB, so plugging them into an USB Type C port would not work.

Newer Thunderbolt/USB 4 devices do not have any technical reason for preventing them to work as USB 3.2 2x2, i.e. to work at 20 Gb/s when plugged into a 20 Gb/s host port, and vice-versa for 20 Gb/s devices plugged into a USB 4/Thunderbolt host port, because both Thunderbolt and 20 Gb/s USB need the same wires in the cable and connector.

I do not know if all USB 4 controllers also work at 20 Gb/s (USB 3.2 2x2), but if they do not work that should be considered a bug.

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by eqvinox on Sunday April 26, 2026 @04:08AM (#47908384)
USB4/TB4 devices doing (only) PCIe tunneling will absolutely not work on a USB3.2 port, or even on an USB4 port without PCIe support (which you can find on some very recent smartphones I believe. It's spec compliant, PCIe is optional.)
Re:New 10 GbE USB adapters are cooler, smaller, cheaper by hypercube33 on Saturday April 25, 2026 @10:49AM (#47901938)
Thats just port speed, charging and other features are all a crapshoot on USB making Thunderbolt the sane version of the "USB-C" family where it requires a set of things (speed, charging wattage)
Re:New 10 GbE USB adapters are cooler, smaller, cheaper by repeekad on Saturday April 25, 2026 @03:13PM (#47903762)
This is not what’s anti consumer, technical specifications can be confusing, it’s cable companies selling at Best Buy “gold plated” “HD ready” “braided fiber” “other bs” that is anti consumer. If you’re thinking about usb versions, you’re far from the normal consumer
Re:New 10 GbE USB adapters are cooler, smaller, cheaper by eqvinox on Saturday April 25, 2026 @10:47AM (#47901919)
> Moreover, "5 Gb/s" is a marketing lie.

It's not a lie, the b just stands for baud not bit ;-)

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by adrian_b on Saturday April 25, 2026 @12:11PM (#47902523)
That is technically correct, but "b" has never been an accepted abbreviation for baud (which was Bd) and the naming of the first versions of the PCIe, USB 3 and SATA speeds, which were done by Intel, were obviously in contradiction with the industry standards and intended to confuse the customers.

Previously to these standards promoted by Intel, the 1 Gb/s Ethernet used the same encoding and it was rightly called by everybody "1 Gb/s", not "1.25 Gb/s", because the gross bit rate has absolutely no importance for the users of a communication standard.

Only Intel invented this marketing trick, calling PCIe 1.0 and 2.0 as 2.5 and 5 Gb/s, instead of 2 and 4 Gb/s, and similarly for USB and SATA, where e.g. SATA 3 is called 6 Gb/s, but its speed is 4.8 Gb/s.

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by Dylan16807 on Saturday April 25, 2026 @04:31PM (#47904335)
The Ethernet version would have been much sillier than that. The megabaud rates for 10/100/1000 Ethernet are in fact 20, 125, and 125.
Re:New 10 GbE USB adapters are cooler, smaller, cheaper by eqvinox on Sunday April 26, 2026 @04:03AM (#47908358)
Yeah, it was a tongue-in-cheek comment. It's a shitshow, and I wish it'd backfire, but it won't. Maybe the EU will come up with some (better) "true labelling" laws, if not I see no chance for this to get better.

(Why the current laws don't cover this, I have no idea. It's technically false advertising.)

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by rewgs on Saturday April 25, 2026 @12:52PM (#47902805)
"gen 2x2" is Microsoft level bad naming.
Re:New 10 GbE USB adapters are cooler, smaller, cheaper by guax on Saturday April 25, 2026 @02:45PM (#47903570)
And USB gen 4x4 is for off-roading.
Re:New 10 GbE USB adapters are cooler, smaller, cheaper by mort96 on Saturday April 25, 2026 @02:25PM (#47903438)
USB 3.2 used to be what we now call USB 3.2 gen 2x2, doesn't it? So it used to be that the version dictated the max speed: 3.0 was 4Gb/s, 3.1 was 10, and 3.2 20, right?

But then they decided to memory hole that and now USB 3.0 and USB 3.1 are also USB 3.2 and USB 3.2 is called "generation 2x2", whatever that is supposed to mean

It makes no sense anymore. It used to be quite simple.

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by Aerofoli on Saturday April 25, 2026 @03:30PM (#47903887)
No, they just renamed things when new standards were released (3.1 and 3.2). 20Gbps wasn't possible before 3.2, and it called Gen 2x2 at the time of release.

5 and 10 Gbps were renamed, though.

5 Gbps first was USB 3.0, then 3.1 Gen 1, then 3.2 Gen 1.

10 Gbps first was 3.1 Gen 2, then 3.2 Gen 2x1.

3.2 Gen 1x2 is also 10 Gbps, but physically different

Re:New 10 GbE USB adapters are cooler, smaller, cheaper by Dylan16807 on Saturday April 25, 2026 @04:27PM (#47904305)
Do any real devices use 1x2? I think we largely escaped that mess and it's mostly a strict progression of 5Gbps, 10Gbps, 10Gbps*2, 20Gbps*2, 40Gbps*2