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DisplayPort 2.0 Now Compatible With USB4, Supports Up to Two 8K Displays or One 16K Display
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Non Alt mode is essentially USB. Alt mode is when you are using alternate signals over the usual USB signal pins and cables.
Non-alt mode means using a USB-C port for USB. Alt modes are modes where the USB-C port is used to pass through different signals, such as in this case DisplayPort.
Ah, thanks, that makes sense. Never heard anyone refer to it that way before.
USB4 has a 40 Gbps mode AND support for Thunderbolt 3, two separate modes. Unfortunately it's not a given that devices will support 40 Gbps, or TB3 with USB4, it is likely laptops will support both (as long as Intel's controllers do). Phones and ARM tablets are not too likely to have either 40 Gbps or Thunderbolt 3 though, as they have historically not needed nor supported Thunderbolt 3.
USB4 is coming soon and will (mostly) unify USB and Thunderbolt
Thankfully, USB4’s changes are internal only—the connectors are still USB-C.
arstechnica.com
Thunderbolt 4 is an unknown at this point. I had heard it could be bumped to 80 Gbps or stick to 40 Gbps. Maybe there won't be a TB4! (well I heard enough rumors that it's being worked on so I think it will happen).
Note that it's using 1 Superspeed lane for 40 Gbps, theoretically they could have made an 80 Gbps mode using both lanes in USB4 (just like USB 3.2 Gen 2x2 which uses both Superspeed lanes). I guess 40 Gbps was decided to be enough for any application using data that's not a video signal. It's odd that USB is okay with using both lanes for video though. But hey, it does mean that DP doesn't really need its own cable any more, it could be USB-C entirely now.
So electric vehicles should be dirt cheap because overall only few people buy them? And the Mac Pro is expensive because demand for it is so high?
When you only sell a small number of units, development costs can be spread only over this small number of units. You'll also be far away from the efficiency of mass production and distribution, increasing those costs as well.
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Alt Mode is using any other protocol than USB 3.x with USB-C ports. TB3 is an 'alt mode' of the USB-C connector. DP is another alt mode of the USB-C connector.
It is "Alternative Mode". The primary mode of a USB socket is USB. There are other data protocols that can be run on the high speed data wire pairs on the Type C socket. Each of those other data protocols is technically an "alternative mode" that gets officially added both by USB-IF (committee) and the data protocol's committee/supervisory org.
This faster DisplayPort mode will probably nominally be also added to the historic main DisplayPort connector. ( Although it may / may not need some physical compliance tweaks and cabling updates. )
Largely with USB standards "Alternative Mode" pragmatically also means optional. It may or may not be there when looking at something with the main USB labeling on it. ( typical USB fashion there is tiny additional iconography on the port that folks are suppose to decode as to what is and isn't there. ). It is far from "if the plug fits then it works" approach.
P.S. Typically the technical Thunderbolt (TB) Alt mode is tightly coupled to DisplayPort (DP) Alt mode being present too. TB v1 and v2 had built in backward compatibility with DP since using DP's sockets. That kind of carried over into TBv3 when the physical socket merged in with USB Type C socket. Some iteration of TB4 ( 4.1 , 4.2 ? ) will probably align up with DP v2.0 and pretty much mandate it is present also.
Thunderbolt 4 is not USB4. It is what Intel is calling Thunderbolt in the new Tiger Lake CPUs (there is no description of how this differs from Thunderbolt 3, there is no mention of USB4 support).
Certain types of USB4 devices require Thunderbolt compatibility (hub/dock) - but hosts is not one of those types:
From the above statements, it seems to me that you can always connect a Thunderbolt 3 device to a USB4 hub or dock. And you can always connect a USB4 dock to a Thunderbolt host.
In the case of a USB4 host, it is not guaranteed that all functions of a Thunderbolt 3 device can be used (whether you connect it directly to a USB4 host or indirectly through a USB4 hub or dock in the case where the host does not support Thunderbolt 3 directly). Thunderbolt 3 uses PCIe (Up/Down) and DisplayPort (In/Out) adapters (an adapter is internal to the controller and is used for inputting or outputting different signals into the USB4/Thunderbolt stream). USB4 adds a new type of adapter for USB.
Adapter types for different USB4 device types:
- USB4 peripheral: optional (all): USB (Up/Down), PCIe (Up/Down), DisplayPort (In/Out)
- USB4 hub: required: USB (Up/Down), DisplayPort (Out), PCIe (Up/Down) (just for the required PCIe switch since a hub may have multiple DFP)
- USB4 dock: same as USB4 hub (I guess a dock is a hub that includes extra functionality such as non-USB-C ports and functionality)
- USB4 host: required: DisplayPort (In); optional: PCIe (Down)
That reference to 80bps could be a muddled reference to including DP v2.0 as a TB standard compatibility mode. Similar to how TB has covered previous updates to DP standards. ( It is just skipping over the directionality of the 80Gbps. )
Thunderbolt peripherals were pragmatically kept down in production because Intel insistent on some minimal quality controls. Needed to pass very substantive Thunderbolt validation checks to be a Thunderbolt product. Intel had the ultimate hammer to enforce those rules because they controlled the flow of Thunderbolt controller chips. No controller , no Thunderbolt. So if don't pass muster with Intel then no controllers for you. End of story.
USB validation checks are much more loose. There are multiple USB controller suppliers so even "race to the bottom" vendors can find controllers to slap onto stuff that isn't being thoroughly test ( got rogue print label and go and sell as much as can before the label "police" show up.) Those race to the bottom pricing vendors typically create oversupply. Generating too much supply could drive down demand pricing. Filtering out race to the bottom vendors is "throttling" to some and "quality control" to others. For example, really were huge checklists of which vendors did or did not have TB cables that worked. Until USB power delivery standards got weaved into TBv3 wasn't much doubt about whether a system host ports worked in TBv1-TBv2.
Economics isn't just one sided. It is the equilibrium of Supply and Demand that sets prices. Primarily looking at it from one side or the other missing the point.
Supposedly USB4 is suppose to change the number of controller supply problem. That may or may not happen quickly. Because Thunderbolt is optional USB 4 controller suppliers could show up and just don't add it to hit lower price points and still claim the base "USB 4" label for their solution. The only devices that will get required to have TB present is a certain class of hub/routers in the middle with multiple "USB4" class ports. If Intel remains the only major player there.... won't change much.
SERIOUSLY. But imagine me with my laughable 4K monitor. The other day, as usual I was looking at it under my microscope, and I thought to myself, enough is enough of this garbage. I need 16k AT LEAST, preferably 16KK.
"...Regarding USB4 support, Intel stated that it is in the design, and they are USB4 compliant at this point, but there might be changes and/or bugs which stop it from being completely certified further down the line. Intel said that it ultimately comes down to the device side of the specification, although they have put as much in as they were able given the time constraints of the design. They hope to be certified, but it’s not a guarantee yet. ..."
https://www.anandtech.com/show/14514/examining-intels-ice-lake-microarchitecture-and-sunny-cove/8
Both Ice Lake and Tiger Lake pragmatically need something to test with that is USB 4 to pragmatically certify as USB 4 . If Intel only tested with Intel's implementation that isn't much of a rigorous compliance test. USB-IF has loosey-goosey testing that not meant to be a high hurdle but need to interoperate with something. It is similar issue to hissy fit some vendors had at the USB 2 transition when Intel was ready to go long before most of the other discrete controller vendors.
Ice Lake may technically miss USB4 because of some cross the 't' or dot the 'i' factor but it is pretty likely that Tiger Lake will hit since that is Intel's stated objective.
licenising cost IF it’s USB-C is zero; apple collects license fees for lightning and Thunderbolt. No machine ships with USB-C 4 currently.
HP Elitebooks are indeed mass market - corporate laptops a large global segment that Apple cannot or does not participate in. If you can to see nor understand that then sorry your thoughts of mass market is way off.
Banking, mining, Higher education etc are many industries their sold into.
Dell, HP and Lenovo each have over 3 Thunderbolt docks they make and sell and this is on-top of the typical after market that tends to market to Apple.
I’d lien to have official numbers for you but I’m sure you know Apple does not sell as many laptops as these top 3 global manuafacturers and sellers.
I love my MBP and prefer Macs. This is simply stating there is a much larger market for Thunderbolt 3 docks and adapters than you believe.
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you’re presuming volumes sold is directly at the retail price. You’re not seeing the price cost being high is due to the licensing per unit sold.
You sort of hit on my overriding point -- USB-C was hailed (by some - not all) as "finally - normal people can just plug things in and they all will work - no more frustration or confusion!"
Of course those of us in here knew better - but the main marketing around USB-C to normal people was much more "finally a solution to the confusion!"
If one has to try to explain to someone that "USB-C is just the port you see" -- the battle is lost right away.
Expect it to be a lot more expensive if it resembles the XDR display, what do you think the casing costs to make, more than you might think, it's probably milled from 1 block of aluminium.
I am aware. I use it myself.
We really do seem to be reaching the limits of copper though. Ethernet is having trouble pushing beyond 40Gb/s as well on the medium.
For relatively short distances. 05m ( ~1 ft ) cables it does work that way if have a high quality ( non race to the bottom) cable. Short means it is a non active cable and if not thinned out to handle 100W power then can do everything ( presuming the monitor has USB-c socket on that side too).
One cable to do everything can work over shorter distances.
Gaps creep in as the cables get longer and the data rate is relatively high. ( or trying to push power over much longer distances. ). The bigger issue is that many folks aren't as focused on the length (and associated constraints ) of the cable as much as "can I jam it in the socket I'm looking at". There is a baseline of different shapes meant "works with that same shape" notion.
It isn't about see it is about quality and length. And reading tiny markings/icons .
Lightning, yes (not sure how that's relevant to this thread). Thunderbolt, no. Thunderbolt used to be specific to Intel chips, but it's now royalty-free.
Elitebooks start at $1,100. That's not the kind of laptop most corporations buy.
In the $1,100-and-above segment, the market shares start to look a lot different.
OK, good.
Intel CPUs packages at the lower end of the laptop/mobile spectrum come with USB4 built in ( so don't have a choice). Those are the most at risk to be flipped over to Apple ARM. The high end of the Mac product line up probably will not have USB4/Thunderbolt built into the CPU (because there is no iGPU there. so not "easing" integration with the TB controller and the DP output stream. ). The PCH ( I/O Chipsets ) on the higher end CPUs tends to lag behind the mainstream CPU+PCH on USB adoption. ( most high end sever rooms don't have huge demands for USB devices. ).
What Apple doesn't have is something suitable for iMac Pro , Mac Pro space. Those are the more likely "last to go".
Addin cards for Mac Pro as also likely to be the "chopped down" USB 4 ( no TB3 and only minimal required USB bus speed update to qualify for the marking) . for the Mac space that probably won't be a good expectation fit.
Again the in the desktop space. Intel may not be offering what can't get with AMD + discrete chip next year.
AMD will be trailing in the laptop space on deep integration.
Apple could just go with TB3 discrete controller and AMD also as an option and just drag their feet on USB4. Basically, did same thing with USB 3.0. They avoided the year one , version one controllers and waited until later.
That was in part to wait until integration with Intel PCH + USB 3.0 merge but if fully intend to dump Intel PCH completely that probably isn't a big motivator. If moving to a new PCH/(I/O chipsset) vendor (e.g., ASMedia ) lomng term then that would more likely be Apple's priority.
Not sure if I am right here, speed over copper seems to degrade fast the longer the cable gets, this problem is far less with Fiber Optics.
Tidbit...Theoretical limit of FO is just north of 1 Petabit
is ARM/Arm suppose to be AMD/Arm or some significance to same word with caps.
AMD has leveraged ASMedia to do their basic I/O connectivity library for them. It would make some sense for Apple just to jump on the same gravy train.
https://www.guru3d.com/news-story/asmedia-600-chipset-family-for-zen-3-available-in-late-2020.html
As to whether Apple gets off of Intel-Mac with USB 4 ... Tiger Lake might have a shot, if only because Ice Lake got one and there may be substantive driver implementation overlap and just cheaper to do.
You're talking about 20 Gbps per lane (four lanes). Thunderbolt 3 has been using 20 Gbps per lane since December 2015. With DisplayPort, all the lanes go in the same direction (in Thunderbolt half the lines go in the opposite direction so it can only be half as fast in each direction).
Question: how is DisplayPort 2.0 data rate calculated? There's a 128b/132b encoding overhead but there is also something else (FEC) that adds slightly more overhead. The conversion factor seems to be between 96.7125 and 96.7129% combined (if you want to convert 10, 13.5, 20 Gbps x4 to 38.69, 52.22, 77.37 Gbps). Does anyone know how the factor is calculated?
Intel could of course call anything for Thunderbolt 4, but as they heavily promotes the USB-C connector, and USB4 new high speed modes are more or less what is today the thunderbolt 3 protocol. It is likely updated to support PCIE4 better. But as it is using the USB-C connector, it would be very difficult to see any bandwidth increase. They have to go to another connector and cable for the additional bandwidth.
Thunderbolt3 is implemented as an USB alternate mode over the USB-C cable, just like DP and HDMI over alternate mode are. USB4 new protocol is more or less that alternate mode, and hosts who wants those will need to implement that.