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Comment by e1ven | Hacker News Reader

I love the idea of USB-C - Being able to have one cable which can do everything is great.

But I've become very leery about actually trusting it in practice - There are so many examples of bad cables, or devices which don't quite follow the specification, causing things to break badly.

If you end up having to follow a defacto "Only use 1st party tools" rule for safety reasons, I'd almost rather manufacturers went back to proprietary connectors. Those aren't inter-operable, but at least they don't pretend to be and risk me breaking everything.

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It's insane to me that you can have two USB-C cables that look exactly the same externally yet provide different(and incompatible!) connections. You can have a USB 2.0, USB 3.0, USB 3.1, Power-only, Display-only, Thunderbolt-3-only "usb-c" cables that all look identical outside yet won't work for your use case. Prime example to me was that the USB-C cable supplied with the MacBook Pro cannot be used to connect the LG displays sold by apple which also use USB-C, and the user gets absolutely zero explanation as to why it doesn't work, no error, no warning - just a blank screen. That's nuts.

> You can have a USB 2.0, USB 3.0, USB 3.1, Power-only, Display-only, Thunderbolt-3-only "usb-c" cables that all look identical outside yet won't work for your use case.

Half of those are not spec-compliant. There are only 4 different legitimate types of cable: 3.0 non-power/thunderbolt, 3.1 non-power/thunderbolt, power-capable non-thunderbolt, and thunderbolt. That's 3 more types than there should be, but let's not make the problem worse than it is.

Wait what.

That is insane. Who thought this would be ok?

Is there any cables that are fullspec?

Yes: Thunderbolt. I only buy those because the $10 extra I spend on a cable now will never matter if I have to deal with this nonsense even once.

Only 0.5M TB3 cables are full spec. Longer ones only support USB 2.0 apparently

Do you have a souce for that? I have a 1m TB3 cable that appears to do USB3.1 just fine, and Newegg sells a 2m one that claims the same. [0]

[0] https://www.newegg.com/Product/Product.aspx?Item=9SIAERN68H8...

https://appleinsider.com/articles/17/08/15/psa-thunderbolt-3... is the first result I found. I could be out of date but I can't find a cable that's 2m long, 40gb, supports 87w+ and USB 3

I thought 0.5M TB3 was for 40G and any longer (up to 2M) is only 20G...

I got downvoted, but I was right:

> At launch, there'll be one passive Thunderbolt 3 cable that supports Thunderbolt, USB 3.1, and DisplayPort 1.2, but with a max bandwidth of only 20Gbps.

https://arstechnica.com/gadgets/2015/06/thunderbolt-3-embrac...

> Who thought this would be ok?

Whoever thought that using the same cable for thunderbolt was Ok. Probably Apple or Intel

Thunderbolt is not even part of the base spec, it just piggy backs on the generic alternate mode that can just as well carry Displayport vidoe (or anything, really).

Most of it is not even with the cables, but the chips and software at either end.

"only" 4???!

Are you sure 2.0 C cables are invalid? Can you back that up?

My favorite is I have an HP Envy USB-C monitor to use with my Macbook, and using the HP factory supplied cable, every time I power it on I get a warning that I should use an "official HP USB-C cable". It's literally the one straight from the box!

I think this error is caused by a mismatch between the monitors capacity to deliver power and your Macbooks desire for it. The HP Envy 27 is rated to deliver 65W, but MBPs want 85W. The MBP will negotiate down to 65W (although the battery may discharge under heavy usage).

I could be wrong though. I've got a similar setup and I've only seen the error once or twice.

My macbook won't wake up my usb-c monitors consistently. I have tried 8 cables at this point. I have to unplug the cable and plug it back in.

I also refuses to mount my phone straight usb-c, and the known workaround is to go usbc -> a -> c.

At this point in my relationship with Apple, I can only assume this is deliberate.

So _that's_ why my monitor doesn't wake up.

I got the new xps13, it only has thunderbolt/USBc-C ports and it's pretty much 50/50 whether my external monitor will wake up.

I figured it was the cable and was about to buy another one but you saved me the trouble.

I also got a hootoo adapter that's supposed to support power delivery but that hasn't worked either :/

This isn't just a problem with USB-C. There are also tons of video adapters on the market that say they support 4k, but really don't. We have grips of 2560x1440 monitors at work, and they had tons of issues like this where the monitors may or may not wake up, may handle the native res for a while, then power down or switch back to 1080p. The only consistent fix for them has been to buy one particular brand of adapter that we found works and making sure it's active. So I guess what I'm saying is, display tech has already been having issues for a long time with crappy components, and USB-C is just adding one problem into the mix now.

What they meant is that you should use an official HP Envy laptop :)

Regular USB had all the same problems. I can't charge my JBL speaker with my iPad charger. And I can't charge much of anything with my older Toshiba laptop USB ports.

Why anyone thought it would be different this time around, I don't know.

Different classes of failure though. Older USB ports would just fail to work (in the majority of cases), whereas with USB-C there is the risk of damaging the device.

That is a different Kettle of fish.

First of all, Apple came up with a slightly different set of resistors on the data pins (leaning that the data in and data out will read slightly different V) to signal to their devices that they could go above 1A draw while charging.

The official charging spec says to put a resistor between the data pins (inside the charger to support detachable USB cables), or simply to short them with a blob of solder.

Your JBL speakers are likely reacting as if it was plugged into a normal USB port.

also keep in mind that the charging spec came about as China and EU wanted to deal with the piles of incompatible chargers that was going into landfills.

Thus older USB ports max out at 5V 0.5A, as that was the spec back when USB 1.0 was launched. Also why some external HDDs come with a Y cable that draws power from two USB ports to get the motor spinning.

what you're describing is simply that those ports were not designed to deliver a lot of amps because usb devices at that time did not need it. i dont think it's the same as not being fully spec compliant at the protocol level. i've never had 2 usb 2.0 devices refuse to work together.

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