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Comment by josho | Hacker News Reader

The solution, I believe, is rather simple. The standards group should require any cable/device with USB 3 support to include a label on its packaging detailing which capabilities of USB 3 are supported.

Think of the nutrition labels on food packaging, instead showing what the device does and does not support, something like this:

Power Delivery——–30w max

Thunderbolt————No support

Bandwidth————–800Mbps max

Video———————4k / 30 fps

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Some of these values are determined only after hooking the devices together. The devices may support 5V/5A (25W) but cable may only support 3A (but it can do 36W at 12V/3A), after connecting the devices you'll get max 15W.

A device using 5V/5A is nonstandard to an ugly extent but that's fine, because the actual spec of the cable is amps and there are only two options: 3 amps and 5 amps.

And we could fold the thunderbolt/bandwidth/video into one single speed rating without much trouble, if the desire was there...

What exactly is non-standard about it?

https://megous.com/dl/tmp/a0538dc39724eb2e.png

https://images.anandtech.com/doci/11181/USB-PD.png

https://i.stack.imgur.com/W8UGp.jpg

Once you hit the soft cap of 3 amps, you're supposed to increase the voltage. The 3-5 amp range is only supposed to be used at 20 volts.

That's all good if your sink supports sinking 20V, but some don't. Anyway, those tables describe minimum required currents for a given PDP:

  https://megous.com/dl/tmp/a4111a84934c8c8f.png

Sources can support more and it's not against the spec, as long as you detect the 5A cable.

  https://megous.com/dl/tmp/1eccbf102295a676.png

> That's all good if your sink supports sinking 20V, but some don't.

It's not like you go directly to 20, you go one step at a time.

> Sources can support more and it's not against the spec, as long as you detect the 5A cable.

They can but how many do? If you want to play nice you shouldn't require that for your device.

That's not going to stop the cheap cables on Amazon from mislabeling their products. This happens all the time today. Off brand HDMI cables pretty much always state specs they don't really support.

But that's not a USB-C problem, that's a consumer protection issue. I'm surprised that we don't have a bunch of class action lawsuits against Amazon for misleading advertising through their marketplace. (yes, I know many of the vendors are the ones to blame, but Amazon facilitates the transaction and is a large target to go after).

Agreed. Pick a set of standards all cables/monitors/chargers/etc. must have and a set of optional standards they can have. So any and all devices you get, all will be at least able to do A, B, and C, and if you need something to do X, Y, or Z, you can clearly see which devices and cables support those more niche needs.

Deciding what is a must have is the more tricky part. I personally think power is a must have. I think every charger and every cable should be able to charge every device. I think having a USB C charger, cable, and device, that it should not even be possible to plug it in and have it not charge because one of those three things does not support the other two.

The problem with that is most people don't keep USB cables in their original packaging. How am I going to know the specs of a particular cable when it's sitting loosely in a drawer with 20 other USB cables?

Fair point, add a QR code tag to the cable that contains the specs. The general point here is that the industry could, and should, be doing something to address consumer confusion.

Much like nutrition labels, this will probably be confusing to the masses to the point of near uselessness, and will mostly be ignored. How many people know the difference between USB 2.0, 3.0, 3.1, superspeed and superspeed+, etc? Furthermore, how will a person know what a cable supports after it is removed from its packaging? You can't fit a table on a cable.

Once you start doing that. How is it any different to using HDMI for Video, Power Cable, and USB for other things?

Using a specific Cable for their own purpose "is" intuitive for vast majority users. Choosing the right USB-C cable is not.

SD cards is a good example, each card lists Generation, Capacity, Sequential writing speed (Speed Class / UHS Speed Class / Video Speed Class), Bus Speed.

Chargers lists Voltage, Current and Power.

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