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Explaining 4K 60Hz Video Through USB-C Hub

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Re: Explaining 4K 60Hz Video Through USB-C Hub

#61

Post by lmm »

janlaureys wrote: post #40
BiteCode_dev wrote: post #36

Earlier quoted context omitted.

I'm completely ok with it being complicated to design and cost 10 euros more if it delivers. And despite all its flaws, USBC does. It's small. It's reversible. I can charge all my devices on it: my samsung tablet, my oneplus phone, my logitech mouse, my jabra headphones, my switch and my XPS 13 laptop, which I can also dock to my screen/ethernet. It's amazing. So yes, I had to take the time to find the proper cable,…

I'm soon switching a lot of things to USB-C. What brands of cables would you recommend ?

Anker. They're consistently reliable, and accessories are their whole business, so a problem would hurt their reputation a lot more than one of the big hardware companies.

Re: Explaining 4K 60Hz Video Through USB-C Hub

#62

Post by cesarb »

nrp wrote: post #20

This issue was the genesis of the short-lived VirtualLink effort: https://en.wikipedia.org/wiki/VirtualLink VR headsets wanted four lanes of DisplayPort, USB 3.1 for data, and power over a single connector, and no existing standard supported that.

I personally believe VirtualLink is dead. Its use case (four-lane DisplayPort and USB 3.x at the same time) is also met by USB4, which I believe will be more widely implemented.

However, I also believe that the VirtualLink trick of repurposing the USB 2.0 pins will end up being used by a future USB standard for two more lanes of USB4, gaining 50% more speed without reducing even more the maximum cable length.

Re: Explaining 4K 60Hz Video Through USB-C Hub

#63

Post by jacquesm »

blattimwind wrote: post #55
pm7 wrote: post #34

Earlier quoted context omitted.

I think in future devices are supposed to support as many popular functions as possible. Due to trend of thin devices we need smaller ports and fewer of them. Multiple possible use of same ports helps. > As a user there is no easy way for me to tell the 12-inch Macbook's USB-C port is different than the Air/Pro unless you explicitly search for it in the tech specs Seems like manufacturer failure. > If you see an HDMI…

> Due to trend of thin devices we need smaller ports and fewer of them. People keep repeating this lie for some weird reason. Similar to the "3.5 had to go because phones are too thin for it" lie. Why? Why do you keep lying? What possible incentive do all these people have? Is it self-deception? "Oh yeah I'm totally fine with losing X, Y and Z because I get thinness and weight reduction in exchange!" You get neither.…

I blame marketing. People will run after every fad as though it is mission critical stuff and will re-tell marketing copy verbatim as though it is their own thoughts. I've seen this with a friend who watches Top Gear a lot, I heard him say something that did not make sense for him to say and tracked it back to a specific episode of Top Gear and confronted him with it. He was surprised himself!

This stuff really works and it gets under people's skins in ways that they are not aware of. If you want to keep an even keel I would like to propose that the only way you will be able to do so is to radically limit your ingestion of any kind of media.

Re: Explaining 4K 60Hz Video Through USB-C Hub

#64

Post by cesarb »

nikanj wrote: post #17
Eric_WVGG wrote: post #16

I saw this headline and was briefly excited for a moment that a USB-C hub finally existed. That is, a device like an ethernet hub or a USB hub, that would turn one port into several other ports of the same kind. This is an article about USB-C port replicators. Four years into this and not a real single USB-C hub exists. I’ve never seen such a botched rollout.

I've been told the USB-C spec doesn't allow for hubs like that.

I've looked at the USB-C spec, and it does allow for hubs like that. The USB 2.0 and USB 3.x parts of the hub are the same as for non-USB-C hubs, and the USB-PD standard even has an example with a 3-port USB-C hub at the end.

Re: Explaining 4K 60Hz Video Through USB-C Hub

#65

Post by ChrisMarshallNY »

I was reading the comments, and saw my exact issue with USB-C reflected there.

I use a Thunderbolt hub (TS3), and I drive a 5120 X 1440 Big Ol' Honker display.

The display has a USBC port, but if I use it, the resolution drops.

I learned to unplug the USBC port, and just use the DisplayPort. If I do that, the display works great. Full width at 60Hz.

It's not a gaming rig, so that's fine for me.

Re: Explaining 4K 60Hz Video Through USB-C Hub

#66

Post by cesarb »

garmaine wrote: post #18
Eric_WVGG wrote: post #16

I saw this headline and was briefly excited for a moment that a USB-C hub finally existed. That is, a device like an ethernet hub or a USB hub, that would turn one port into several other ports of the same kind. This is an article about USB-C port replicators. Four years into this and not a real single USB-C hub exists. I’ve never seen such a botched rollout.

USB-C hubs are not permitted by the spec.

Where in the spec is it written that USB-C hubs are not allowed? The USB-PD spec even has an example with a 3-port USB-C hub, showing how the power delivery negotiation with the downstream ports should work.

Re: Explaining 4K 60Hz Video Through USB-C Hub

#67

Post by treyfitty »

Last night, I was ready to pull my hair out trying to figure out what dock + cable I need, so this article is quite the blessing. However, I’m still left confused on whether I need a USB3.1 usb-c cable or Thunderbolt 3 cable.

In light of the MBP16 announcement, I wanted to plan my purchase, including the peripherals. I currently have 2 4K monitors on a PC. I’d still like to use that PC from time to time, but it’d be convenient to do so through a dock. Enter the Targus dock that I happen to have received through work (https://www.amazon.com/dp/B07BPQKP8V/ref=cm_sw_r_cp_api_i_0b...) which claims to be Thunderbolt 3 “compatible.” However, none of their ports are specced to be such. Furthermore, the included host attachment USB-C up cable is only capable of transferring 5GB/s instead of the 40GB/s a la Thunderbolt 3.

Now, this article explains DisplayLink nicely, but what happens when I use the Targus Dock with and without a Thunderbolt 3 cable? Does it bypass DisplayLink and just go directly to the dual 4K monitors at 60hz? Or does it still fall victim of CPU overhead due to processing DisplayLink?

Re: Explaining 4K 60Hz Video Through USB-C Hub

#68

Post by _trampeltier »

phire wrote: post #35
wavesquid wrote: post #8

The HP ZBook Dock with Thunderbolt 3 tends to be on ebay for around US$50 and should do 4K 60Hz.

Avoid that one. There is a reason why it's so cheap on ebay. Sure, it's a Thunderbolt 3 dock, but the two displayport ports aren't using thuderbolt 3. The are actually connected via USB displaylink.

Uh, yes. Avoid that one. We have ZBooks and these Docks at work and we all have all kind of troubles. But the funny thing is, we all have different troubles. Mostly the keyboard or one or two monitors does not work ..

Re: Explaining 4K 60Hz Video Through USB-C Hub

#69

Post by Nextgrid »

wslh wrote: post #58
Nextgrid wrote: post #26

The USB-C spec is an insane mess. The fact that every port used to be different is actually a feature, as it helps you identify which device supports what based on the ports it had. If you see an HDMI port on a laptop you can be sure it's going to output some kind of video signal over that. If you see Thunderbolt then you're sure the machine supports Thunderbolt. USB-C just jams all these incompatible standards into…

Once this is sorted out we would have a wonderful world. Using a single Thunderbolt port I connect my notebook to a dock and immediately convert the small notebook into a desktop with three external monitors plus many other ports. I can also magically use the same USB-C hub I use in the notebook in my mobile phone to add a keyboard and mouse plus an HDMI monitor. I have never seen this in the past: my previous notebo…

That world will not happen unless every single device including entry level phones and size-constrained devices somehow magically include all the circuitry required to handle all the different alternate modes.

Also, as far as I understand there just isn’t enough pins to support all the modes at once so trade offs have to be made...

Re: Explaining 4K 60Hz Video Through USB-C Hub

#70

Post by tlamponi »

Nextgrid wrote: post #69
wslh wrote: post #58

Earlier quoted context omitted.

Once this is sorted out we would have a wonderful world. Using a single Thunderbolt port I connect my notebook to a dock and immediately convert the small notebook into a desktop with three external monitors plus many other ports. I can also magically use the same USB-C hub I use in the notebook in my mobile phone to add a keyboard and mouse plus an HDMI monitor. I have never seen this in the past: my previous notebo…

That world will not happen unless every single device including entry level phones and size-constrained devices somehow magically include all the circuitry required to handle all the different alternate modes. Also, as far as I understand there just isn’t enough pins to support all the modes at once so trade offs have to be made...

I can plug in a X1 carbon thinkpad in my monitor (some ultrawide dell) with USB-C support just fine. I then get video, audio, USB (the monitor has a hub where I have mouse and keyboard connected) _and_ charging/powering my laptop over a single link.

Works today with Linux here! It's just magical, I tell you.

The world started to happen already, it may not become all that good and 100% universal soon or anytime, but good enough for a wide spread adoption.

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