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Comment by qwerty456127 | Hacker News Reader

I wonder if one day Thunderbolt+DisplayPort+USB hybrid (what some Type-C ports of today already are) will become the only connection interface we will use. It can replace HDMI (with a small and cheap adapter for HDMI-only displays), PCIex slots, OCuLink (not really an expert on these but why not?) and obviously SATA which already falls out of relevancy quickly. So why do we even need anything but full-featured Thunderbolt ports?

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It's one of those ideas that sounds really good, but winds up being a bit of a nightmare. Just looking at what we currently have with USB-C things get very complicated. A USB-C port can support one of several different speeds of USB or Thunderbolt. It may also support native Displayport alternate mode or it may not. That's just the ports. The cables become even more tricky. Even if you know your USB-C/Thunderbolt port is capable of Displayport, is your cable capable of it? Most USB-C cables out there are USB 2.0, because it's way cheaper and many users only care about charging their phones or the occasional file copying. Even if you do have the right calbe it may only support lower bandwidth so now you're stuck trying to figure out why you can't do 4K60P. Now how do I explain all of that to a less technical user?

> Now how do I explain all of that to a less technical user?

"You need that expensive cable labelled as USB4 to do anything other than charging your phone".

IIRC these things depend on the port and the cable supporting it. If so, we'll have a universal form factor for all sorts of functions that depend on the capabilities of the port and the cable both being clearly labeled which, in practice, are requirements not always satisfied (or understood by most users). For the most part in the past there was one cable that did one thing, fit one specific port, and basically did what it was expected to do without any fuss.

I expect more confusion and frustration from non-power-users.

I believe most of the people writing here (let alone those using OCuLink) can afford always buying the best full-featured cables to avoid the problem entirely.

For those who can't afford this the whole problem can be solved by better labeling of the cables.

Whatever the case, to me this doesn't seem a reason why we should keep different ports for everything on actual computer mainboards when there is thunderbolt.

If a mainboard manufacturer is worried about end-users being unable to get proper cables - just put some in the box.

im not necessarily opposed to it, but there are tradeoffs that come with a universal port. USB consortium tried to fix this with the coloroed tongues inside the female piece, but either manufacturers thought they were ugly or the number of different functions outstripped the colors your could reasonably use.

i doubt think many on HN will have trouble with this, except when their family asks why it doesnt work when the cable is plugged in and cant read the fine print on the sheath.

The only drawback is that Thunderbolt is fairly expensive and the cables are very expensive.

Thunderbolt cables are just USB-C cables. Some cheap cables may not have all the connections needed but ff you are getting a cable rated for USB4, it will work for Thunderbolt.

Not really. USB-C 3.0 cables are $10-20 while Thunderbolt/USB4 cables are $30.

A SATA cable is $2-3 so replacing SATA with Thunderbolt would increase cable costs by literally 10x.

I just wonder what the actual production price is. Perhaps Thunderbolt cables only cost this much because of being a luxury segment - nobody but rich people buying expensive peripherals for their expensive computers really need them today so why not charge them another $30. Maybe the price will drop substantially once most of the consumers will need them.

> Some cheap cables may not have all the connections needed

Well yeah, that's pretty important. A 2m cable that supports 40gbps from a reputable vendor is $59 (https://www.amazon.com/dp/B084Z65YJQ/), and that's one of the better prices I've seen. There's a bunch of no-name ones for around $50, but I'm not sure I'd trust them.

>getting a cable rated for USB4, it will work for Thunderbolt.

While USB4 does mandate the use USB-C connector, support of Thunderbolt is not mandatory and is entirely optional.

> and the cables are very expensive.

Define expensive to you? It’s cheap enough to me that I buy Thunderbolt cables exclusively as they have the most universal support for all the USB-C alt modes and PD variations.

Even if you can get them cheaply the length limits on non-“active” thunderbolt 4 cables make them a poor choice as a universal replacement for a usb c cable in many cases. Unless you have active cabling (hundreds of dollars or more typically for thunderbolt 4 and extremely rare) the Thunderbolt 4 spec maxes out at 2m for passive cables. You can have other flavours of USB C cable in longer lengths and still conform to spec.

I’m in no rush to replace my laptop charging cable with a 2m one. Similarly, I use a ~5m usb c cable for a VR headset.

> I’m in no rush to replace my laptop charging cable with a 2m one

That’s the beauty of having choice. I have zero need or desire for a longer than 2m cable for my laptop.

I guess it is pretty difficult and expensive to make on both sides from a notebook or on front and back on a pc very fast ports.

Dual USB-C[1] can also replace NEMA-1 power connectors.

[1] https://m.xkcd.com/2493

We already have one serial signalling method being "pan-standard." It's single mode optics transmission.

Optic transmitters already don't care what data exactly, and how is sent through them. The electrical interface in between them, and the main chip is a dumb SERDES, and it does exactly nothing except sending the data as-is.

Once on chip, the signal is free to be routed without any special electrical modulation as one wants.

Plain SFP+ transmitted are used from Ethernet, to FibreChannel, to Infiniband, to SONET, to 4G CPRI, to HDBaseT. Both fibre, and optics actually got really, really cheap.

Some ISPs even transmit DVB-T2 over the same optical cables thy use use to provide the actual Internet connection.

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