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USB4 Specification Merges Thunderbolt 3 and USB With Transfer Speeds up to 40Gb/s

technoholic said:
Here's an example - my LG Ultrafine 5k display came with a cable, I presume a TB3 cable. I would expect that I can't use a USB Type C non TB cable to connect my Mac to the monitor, which is the case. But why does my TB cable not work to connect my Mac to a different monitor that supports USB-C for video, i.e. my current LG 27UK850? Surely if TB3 is a superset of USB 3 then it should work right? it would be great if someone could explain that to me
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Thunderbolt 1/2, and Thunderbolt 3 40 Gbps (but not 20 Gbps) all require active cables due to their high speeds. Those cables are not compatible with non-Thunderbolt devices, because those don't know how to deal with the chips in the cable.

TBT3 20 Gbps runs over a passive cable that is backwards compatible with USB 3 speeds.
 
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konqerror said:
Thunderbolt 1/2, and Thunderbolt 3 40 Gbps (but not 20 Gbps) all require active cables due to their high speeds. Those cables are not compatible with non-Thunderbolt devices, because those don't know how to deal with the chips in the cable.
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Excellent, just what I needed to know, and yes the cable with the 5k is an Active cable so that make perfect sense.

It just goes to show how confusing it can be. So if I want 1 type of cable to use for everything and be the best it can be, then providing I don't need TB3 40Gbps then a passive 20Gbps TB3 should support pretty much everything, right?
 
technoholic said:
So if I want 1 type of cable to use for everything and be the best it can be, then providing I don't need TB3 40Gbps then a passive 20Gbps TB3 should support pretty much everything, right?
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TBT3 20 Gbps cable that supports 5 A (100 W) USB-PD charging. The trade-off being those cables are thick and short.

I agree USB-IF and the quest for cheap totally made a huge mess. We don't have to flip the cables anymore at the expense of not having the right one and no way to tell.
 
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H3LL5P4WN said:
Actually, I wish they'd have redesigned the connector and port so as to leave this floating dumpster fire that android OEMS made "USB-C" into behind us.

giphy.gif
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When lowest cost is THE driving engineering mandate, it’s going to be a CF no matter what connector they use. The only way it works is if the connector protocol, power delivery and every single detail is set in stone and not subject to allowing for a “scaled back” implementation as they will choose it every single f***ing time to save 5¢ a damn unit.
 
Active Thunderbolt 3 cables currently have a maximum cord length (copper) of 2.0m when operating at full capacity 40 Gb/s [4 lane] and only 0.5m when passive (copper). Will be interesting if USB4 makes up to 60m (optical) cables more common.
 
pzo said:
Meanwhile iPhone XS still provides only USB 2.0 transfer speed :(
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This is extremely frustrating. I take a lot of videos on my iPhone, and i don't use any Mac devices.i have to transfer the videos to Win10 and this is extremely horrible, takes a long time and often fails. I then usually have to resort to slowly upload the content to cloud storage
 
oneMadRssn said:
Don't get me wrong, I like USB-C, but it is not the panacea everyone makes it out to be. There is not "one cable." There are a large number of different USB-C cables, all with different specs, speeds, etc.

...

Basically, USB is still a spaghetti of specs and limits, and this is just adding yet another layer. Just because the physical plug of Type C is nice, does not mean all the other USB problems are solved.
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This, a million times.

What the USB-IF has done is solved the physical compatibility problem by adopting a single connector, USB-C, but in the process made all other respects much worse, merely shifting the technical complexity to cables and protocols, and potentially confusing even for folks who try to keep up with it.

The lay user stands no chance, nor are they likely to care either, about speeds, watts, wire gauge, length etc.; as long as the plug and socket mate, and a connection is made.

In that respect, USB-C has been a great success, but the rest is a fustercluck, with a marketing scheme developed by and for nerds (first with the Gen nonsense, and then backtracking on it), not consumer marketers.

A classic example of "by committee," and all the negative connotations that carries, if ever there was one.
 
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warrenr said:
TB4 is still firmly in the land of guesswork and speculation at the moment. There's been no news or leaks from Intel at all.
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Before Intel does anything with Thunderbolt 4, they need to move to PCIe v4.0, allocating four lanes as they do with Thunderbolt 3 and PCIe v3.0. The bandwidth provided would be plenty for a GPU and and an NVMe SSD at the same time.
 
steve23094 said:
Any clue if Thunderbolt 3 will be forward compatible with USB4? (ie get 40gbps with USB4 devices connected to Thunderbolt 3 ports).
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Read the PDF specification. It's very clear.
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goobot said:
I remember 10 years ago on this site when thunderbolt was first announced as lightpeak and was said to have 100Gb/s.
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It will once PCI-E 6.0 arrives. With PCI-E 5.0 already finalized and 6.0 in draft status it's will be out probably in 3-4 years from now.

On June 18 2019, PCI-SIG announced the development of PCI Express 6.0 specification that will double the data rate to 64 GT/s, yielding 128 GB/s in each direction in a 16 lane configuration, with a target release date of 2021.[65] The new standard uses 4-level pulse-amplitude modulation (PAM-4) with a low-latency forward error correction (FEC) in place of non-return-to-zero (NRZ) modulation.[66]
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Textime said:
Yes yes more transfer speed for 128GB laptops!
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Maybe for PCs! But MacBook Pro currently have Thunderbolt 3 and have had for years, so they won’t be getting any faster.

And whether you have 128GB or 4 TB of PCIe SSD capacity internally, 40Gbps Thunderbolt 3 ports are awesome for connecting external SSD drives. Would recommend Samsung X5 series.

btw even the bottom of the line MacBook Air has multiple TB3 ports.

Thanks Tim Apple!
 
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konqerror said:
According to the spec, it's optional



Skimming the relevant sections, there's a number of minor implementation details that are different between USB4 and TBT3.
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The only thing I learned is to stay out of USB-C / USB / TB discussion. Thank you Konqerror for continuing explaining everything,

By the way there will also be an updated USB-C specification, I don't have time to read the what news and why yet.


PickUrPoison said:
Maybe this year’s iPhone 11 models will support USB3. Apple may tell us next week, or we might have to wait for testing :eek:
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Likely not, I have yet to see a controller chip supporting USB 3.1 transfer speed in the size of current controller chip and at a cost that is cheap enough to make the jump. People constantly point to iPad Pro for USB-C and Transfer speed, as well as power delivery completely neglect the fact the controller on iPad Pro is many times the size and I don't see how Apple want to do that on iPhone. I would love to be wrong though.
 
Also the question is whether usb4 will be full 40Gb/s or like tb3 22Gb/s + 18 reserved
 
How about power adapter with multiple (like 5 or 6) usb-c ports?
Right now I still need to use usb-a cables to charge all equipment beside macbook pro.
 
ksec said:
Likely not, I have yet to see a controller chip supporting USB 3.1 transfer speed in the size of current controller chip and at a cost that is cheap enough to make the jump. People constantly point to iPad Pro for USB-C and Transfer speed, as well as power delivery completely neglect the fact the controller on iPad Pro is many times the size and I don't see how Apple want to do that on iPhone. I would love to be wrong though.
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Well, if it’s not feasible to move from USB 2.0 to 3.1 due to cost or size/power requirements of the host controller interface, and you’re not going to offer display port alt modes, then there’s really no reason to transition from Lightning to USB-C on iPhone. There’s little to be gained.

But Apple could add USB 3.1 controller functionality on the SoC if they choose. The IP is available for license, Cadence for instance offers Fresco Logic’s USB 3.0 and 3.1 xHCI. Instead of a 6mm x 6mm discrete TFBGA package like the iPad Pro has, it would then have a much smaller footprint, who knows maybe 3x3mm. Since the iPhone 8/X, iPhones already have a USB-PD controller.
 
So forgive my stupidity but is USB4 basically just rebranded Thunderbolt 3?
or are their other enhancements ?

I’m wondering because they say USB4 due late 2020. if it is just TB3 why would it take a year?
 
Zdigital2015 said:
When lowest cost is THE driving engineering mandate, it’s going to be a CF no matter what connector they use. The only way it works is if the connector protocol, power delivery and every single detail is set in stone and not subject to allowing for a “scaled back” implementation as they will choose it every single f***ing time to save 5¢ a damn unit.
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I thought that was the point of standards.
 
H3LL5P4WN said:
I thought that was the point of standards.
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Not when you let political pressure from certain members impede the standards, you water things down to appease them by making things optional to insure their buy-in and then you have a mish-mash of incompatibility that confuses customers and causes real problems. Genuinely, the race to the bottom by PC OEMs and now mobile OEMs just causes no end to these headaches.
 
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macnylonguitar said:
Finally,

I am hoping this is the "last straw" that makes Thunderbolt a "standard" and widely adopted IO technology.

Companies have been reluctant to adopt it due the high priced licensing that Intel imposes on its licensees for Thunderbolt. So Intel can and apparently is just "pivoting" using USB4 = free TB3.

So that could explain "where the heck are all the TB3 devices"?, and the answer has been, nowhere, not gonna happen, due to those high license fees.

I have seen TB3 on Dell laptops, and of course Apple will just stick with TB3, but...

perhaps we will finally see USB4 / USB-C cables, external drives, etc all over the place and at reasonably cheap prices.

USB4/USB-C could finally be the answer as far as ubiquity, cheap cost, and fast speeds.

And of course, no brainer, iPhone 11 has to have USB-C connector / port...
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Intel announced it was moving TB to royalty free in May 2017...
https://bit-tech.net/news/tech/peripherals/intel-thunderbolt-3-licensing/1/
https://www.techradar.com/news/intel-has-a-grand-plan-to-bring-thunderbolt-3-ports-to-every-laptop
 
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