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How many kinds of USB-C to USB-C cables are there?

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Re: How many kinds of USB-C to USB-C cables are there?

#41

Post by solarkraft »

wmf wrote: post #25
BluSyn wrote: post #12

Does anybody know how USB4 will impact this? Will any cable that will be labeled as USB4 need to be full spec, or will there be a similar situation of cables with varying degrees of compatibility all labeled USB4?

If we assume that USB4 is basically Thunderbolt 3 that means full spec cables will be too expensive so they will definitely allow lower-spec cables. And if it keeps using the USB-C connector then all the bad old cables are still there.

IIRC USB4 is planned to be exactly Thunderbolt 3.

What is needed is an easily identifiable branding, which I have some hope left USB4 will finally provide.

Re: How many kinds of USB-C to USB-C cables are there?

#42

Post by starsinspace »

After buying a screen which has only a USB-C DP-Alt-Mode input, I was recently in the market for a matching cable. My only requirements were “it should be as long as possible, at least 2 meters” and “it needs to support DP-Alt-Mode”.

Now I thought this would be easy, just ask Google what kind of cable I need, right...? Well... no. Not at all. I wasn’t able to find any information whatsoever what kind of USB-C cable is needed for supporting Alt-DP-Mode. I guessed (really guessed, couldn’t find information) a USB 2.0 USB-C cable wouldn’t be good enough. But is a 5Gbps cable enough? Or is a 10Gbps cable needed? Or maybe neither and I need to buy one of those really expensive USB-C Thunderbolt 3 cables...?

In the end I just bought a 2 meter USB-C 3.2 5 Gbps and just hoped for the best. And indeed it works. Yay!

The thing is... I’m a technical person, and even I can’t figure this out. How is a non-technical person supposed to navigate this?

And by the way: one piece of information I did find about USB-C and Alt-DP-Mode is that the current spec for Alt-DP-Mode doesn’t allow use of active cables, so length is limited to 2 meters. That’s another pitfall restriction.

Re: How many kinds of USB-C to USB-C cables are there?

#43

Post by TorKlingberg »

gok wrote: post #18
TorKlingberg wrote: post #14

I have never encountered a C-to-C cable with only USB 2 support. Are they are really a thing?

Most are in fact. When I searched for "USB C cable" on Amazon just now, I had to scroll to the 16th result to find a non-USB2 C-to-C cable.

When I search for "USB C cable" on Amazon UK, 90% of the results are A-to-C cables. The first C-to-C cable is an Amazon Basics 2.0 cable, so you are right.

Re: How many kinds of USB-C to USB-C cables are there?

#44

Post by AnIdiotOnTheNet »

derekp7 wrote: post #40
AnIdiotOnTheNet wrote: post #17

Earlier quoted context omitted.

You ever wonder what the purpose of keying connectors is? I'm curious, because it's one of those time-tested ways to ensure that things get plugged into the correct ports and avoid costly accidents. Really simple too. Why on earth is a standard as ridiculously complicated as USB-C a better idea? What is the practical value of an "everything" connector when its spec is so complicated that it really doesn't support "ev…

For low volume production items, the plastics are more costly to design than the electronics. Therefore laptop docking stations are expensive to manufacture, especially as they are in use by only a subset of users. By converting to a docking station that requires a simple small plug for everything, that makes them much cheaper. Instead of making a huge chunk of plastic that the laptop has to click into.

That explains why laptops should have a standardized "docking station" port, not why that port needs to also support literally everything that runs on electricity with the ability to also channel high-current power in both directions.

Re: How many kinds of USB-C to USB-C cables are there?

#45

Post by chx »

TorKlingberg wrote: post #14

I have never encountered a C-to-C cable with only USB 2 support. Are they are really a thing?

Yes and since they are very thin they are quite useful when you just want to carry a tiny charger (my choice is the Mu One / RAVPower GaN 45W same Navitas charger except the Mu One has nifty folding international heads) and a lightweight cable. AmazonBasics is a reliable brand for this.

Re: How many kinds of USB-C to USB-C cables are there?

#46

Post by mmastrac »

There's always pain after a USB spec gets released. This has been pretty much par since USB 1.0 - switch chips were flaky back then, USB drives were quirky and getting them working on anything other than a specific version of Windows was a crapshoot, etc.

Eventually all-in-one chips get less buggy, cable manufacturing gets cheaper and we move on to the next spec level and repeat.

Re: How many kinds of USB-C to USB-C cables are there?

#47

Post by Yizahi »

msbarnett wrote: post #29
manacit wrote: post #13

I've had a USB-C capable device (MBP) for a few years now, and it originally was extremely annoying. Needing dongles for _everything_ was annoying, and getting rid of Magsafe meant a lot of my existing chargers that I'd accumulated no longer worked. My work laptop (at the time) didn't use USB-C, so I had to keep two chargers around, and I couldn't charge my iPhone from my laptop at all. Fast forward a few years and I…

With a MacBook Pro it’s not so bad, because rather than try to save a few cents Apple wired every USB-C port for everything that it supports, so there’s no real distinction between ports (but you still need to distinguish between very similar looking cables that handle, say USB 3.0 in one case and an active TB3 40 Gbps in another) It’s at the low end of the market that USB-C is an entire mess. This port on your lapto…

Except that even Apple forgot certain options in their 50$ USB-C charger and it is therefore non-compliant with specification. Apparently USB-C is hard.

source: https://twitter.com/USBCGuy

Re: How many kinds of USB-C to USB-C cables are there?

#48

Post by mjevans »

I did NOT know about the Tree, SS Tree, and SS Tree 10 logos actually meaning something, but if that's what's required roughly a quarter of the problem solved.

Another quarter would be mandating clear markings for the Power Delivery capability: I suggest PD{amps}A OR PD{watts}W as text markings, and also the use of some color code; yes both.

The other 50% of this would be to REQUIRE that marketing use specific terms so that search engine results would be useful and to BAN re-use of those same terms if a feature is not supported.

Ideally that last step would include a suffix 'max' for indicating the highest supported tech protocol.

E.G. the current cable could claim (some lesser modes skipped) USB SuperSpeed, USB SuperSpeed 10 max, PD3A, PD5A max, PD15W, PD60W, PD100W max

While a lesser cable might drop bits from the enumeration of the specification. It would also allow searching by a wattage/amperage (in case it matters: E.G. some devices might support 5A but not the higher volts, others the reverse).

Re: How many kinds of USB-C to USB-C cables are there?

#49

Post by Havoc »

This is a complete and utter failure of standard setting bodies.

From a consumer perspective there is no discernible standard to speak of.

On the plus side the reddit spreadsheet (!!!) about these cables ffritz posted suggests most charge at either 60 or 100W which is fast enough so I'll just avoid USB C for data transfers entirely

Re: How many kinds of USB-C to USB-C cables are there?

#50

Post by Dylan16807 »

claar wrote: post #15

I wish they would have also discussed how this relates to Thunderbolt 3, which I believe would add at least two cable types: "7 (TB3 passive)" and "8 (TB3 active)"... of course I'm probably completely misunderstanding this crazy labyrinth of lookalikes. Here's a lovely statement regarding TB3 from an online FAQ: Are all Thunderbolt 3 (USB-C) cables created equal? No, in fact, there are two types of Thunderbolt 3 (USB…

Thunderbolt gets to be an entire extra dimension, thanks to cables that support thunderbolt but not USB 3.
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