"Transfer rates of up to 40 Gbps (5 GBytes/sec)"

3.8GB/s (3.938GB/s with 128b/130b encoding).
Hate fake marketing.

Asni"Transfer rates of up to 40 Gbps (5 GBytes/sec)"

3.8GB/s (3.938GB/s with 128b/130b encoding).
Hate fake marketing.

Yeah, and while I will admit that I'm not sure how it works for USB4, but at least for Thunderbolt 4, that "40Gbps" number is misleading as it represents the COMBINATION of data (32Gbps/PCIe 3.0x4) and other protocols like displayport (which add in the 8Gbps) reach the 40Gbps, but if you hook up any kind of storage device, you'll never achieve data rates faster than 32Gbps.

I don't know how USB4 works, but I'd assume a lot of it is dependent upon what the host device uses to support that USB4 port, i.e. whether it's an ASMedia controller and how many PCIe lanes connect and what generation etc., but yeah it can be very misleading especially for casual consumers.

I

I wonder what USB-NVMe bridge they're using?
(Must be, since not all USB4 supports PCIe encapsulation)

I'm only familiar with Gen3-back bridges.

AnarchoPrimitivYeah, and while I will admit that I'm not sure how it works for USB4, but at least for Thunderbolt 4, that "40Gbps" number is misleading as it represents the COMBINATION of data (32Gbps/PCIe 3.0x4) and other protocols like displayport (which add in the 8Gbps) reach the 40Gbps, but if you hook up any kind of storage device, you'll never achieve data rates faster than 32Gbps.

I don't know how USB4 works, but I'd assume a lot of it is dependent upon what the host device uses to support that USB4 port, i.e. whether it's an ASMedia controller and how many PCIe lanes connect and what generation etc., but yeah it can be very misleading especially for casual consumers.

USB4 can deliver the full 40 Gbps, assuming the host controller supports 40 Gbps data rate and has a wide enough system interface. This assumes you're only using the USB4 interface for data.
The ASMedia ASM4242 can do 40 Gbps on one port, but not both simultaneously, due to its PCIe 4.0 x4 interface being the bottleneck.
www.asmedia.com.tw/product/e20zx49yU0SZBUH5/363Zx80yu6sY3XH2

LabRat 891I wonder what USB-NVMe bridge they're using?
(Must be, since not all USB4 supports PCIe encapsulation)

I'm only familiar with Gen3-back bridges.

One of the two variants from ASMedia?
www.asmedia.com.tw/products-list/d8cyq6FXzaUH8XJa/C64ZX59yu4sY1GW5

Also, neither of you read my article about USB4 from last year? :(
www.techpowerup.com/review/usb4-guide-info-technology-details/

TheLostSwedeUSB4 can deliver the full 40 Gbps, assuming the host controller supports 40 Gbps data rate and has a wide enough system interface. This assumes you're only using the USB4 interface for data.
The ASMedia ASM4242 can do 40 Gbps on one port, but not both simultaneously, due to its PCIe 4.0 x4 interface being the bottleneck.
www.asmedia.com.tw/product/e20zx49yU0SZBUH5/363Zx80yu6sY3XH2


One of the two variants from ASMedia?
www.asmedia.com.tw/products-list/d8cyq6FXzaUH8XJa/C64ZX59yu4sY1GW5

Also, neither of you read my article about USB4 from last year? :(
www.techpowerup.com/review/usb4-guide-info-technology-details/

IIRC, your article was one of the things that had me excited for USB4.

USB4 Tunnelling and DP Alt Mode

One of the key advancements with moving from USB 3.2 to USB4 is something referred to as Tunneling. The short version of what tunneling allows is a means of sending multiple different protocols simultaneously over the USB4 fabric. The longer version is that USB4 allows for not just USB data to be sent, but also PCI-Express and DisplayPort signals. Until the signal reaches an endpoint, such as a DisplayPort monitor, the signal is sent as encapsulated data within the USB data stream, and the actual DisplayPort signal only gets extracted once it reaches its destination. This is similar to how Thunderbolt works.




Unlike DP Alt Mode, which physically takes over two wire pairs of the four pairs in a USB Type-C cable for exclusive use for DisplayPort signals, tunneling allows the DP 1.4 signal to be transmitted simultaneously with USB4 or PCIe signals. At higher resolutions and refresh rates, DP Alt Mode can even use all four data pairs in a USB-C cable, which means USB data transfers are limited to USB 2.0 speeds over a separate set of low-speed wires inside the USB-C cable. When tunneling is used for DisplayPort 1.4 signals, DP will be prioritized over USB and PCIe data, due to a display signal being isochronous in nature, which means that an interruption to the signal would prevent a picture from being displayed on the screen. Although tunneling doesn't solve this for high-resolution/high refresh rate displays today, future versions of USB4 should have a solution for this that still allows for high-speed data transfers. Note that Display Stream Compression (DSC) can be used to save bandwidth for the DisplayPort signal when tunneling is used.

...and since that write-up, the few USB4 options I'd looked into, supported/implemented (pretty much) none of that.
Edit: Apparently, the AM4 board w/ USB4 that I swear I'd researched; never existed. That was my ref point, and The Internet is telling me it's a false memory

It's not your fault USB-IF and ODM/OEMs make this exceedingly difficult. Example:

A key thing to note is that the standard is called "USB4," not "USB 4.0" or "USB 4," and the USB-IF actually has two marketing names for USB4, namely "USB4 20 Gbps" and "USB4 40 Gbps." The technical names are "USB4 Gen 2x2" and "USB(4?) Gen 3x2," but there's also "USB4 Gen 2x1" and "USB4 Gen 3x1," both of which are fallback

So, that allows AIBs and ODM/OEMs to sell "USB4" branded devices, that cannot even do the 'new baseline speed' of 20Gbps. (like what happened with USB Type-C* and USB 3.1->3.2)
*Yes, I'm well-aware USB-C is a just physical/interconnect standard. However, that's not how it was 'sold' to the market. The promise of "one connector to rule them all" turned into a quagmire of highly-varying implementations and poor accessory quality (IMHO: due, in large part to such 'loose' technical specifics.)

Also, your mention of so few USB4 controllers on the market/ever to be made, makes me think USB4 as a whole is just about DoA (for consumer-enthusiasts).
Basically, it looks like its gonna get the 'firewire' treatment (having few, if any fully implemented integrations on the PC platform). Ending up largely relegated to 'professional media industry' and Apple.

Addendum: I'm probably mostly jaded, since USB4 feels like we were supposed to have it 2 years ago. In fact, I can find rumblings in 2020 about USB4...
So, I'll admit to a sour attitude tinting my PoV; and I should really reserve judgement until AFTER ASM4242 sees full market-availability.
(I edited after reading specs on ASM4242, and it promises to be my every expectation and more.)


Edit 2:
Looks like there was some implementation on some 6000series APU option Mobile PCs. (at least after Firmware updates) Author also goes over early 'USB4 advertised' non-USB4 devices.

edit 3:
@8:33 in the video, he mentions that Microsoft Sticker-Certified Windows 11 laptops marketing USB4 port, must support PCIe tunneling.
Previously and by demonstration, 'not-actual-USB4' devices had me thinking otherwise.
Note: He does emphasize right afterwards how PCIe Tunneling is still an optional feature.

Everything USB4 got delayed by about a year, courtesy of shall we say, poor documentation from the USB-IF that assumed a lot of things that would only be inhouse knowledge if you worked at a certain company. Hence why a lot of things never ended up being delivered on time.

TheLostSwedeEverything USB4 got delayed by about a year, courtesy of shall we say, poor documentation from the USB-IF that assumed a lot of things that would only be inhouse knowledge if you worked at a certain company. Hence why a lot of things never ended up being delivered on time.

Thank You.
At least my sour feelings are not entirely w/o basis in reality.

As long as yields are good, and adoption wide, those Host and Device options from ASMedia are looking extremely attractive.

ASM4242
Integrating ASMedia’s self-designed physical layers (PHYs), this controller is implemented with USB4 router including the time measurement unit (TMU) and several PCIe downstream/DisplayPort IN/USB downstream adapters, PCI Express switch, DisplayPort retimer and Intel® eXtensible Host Controller Interface.

I'd love to slot-in an ASM4242-based PCIe Gen4x4 USB4 card into my X570
(even better if 4-ports using 2 interlinked via PCIe Switch ASM4242s, too :laugh:).

LabRat 891So, that allows AIBs and ODM/OEMs to sell "USB4" branded devices, that cannot even do the 'new baseline speed' of 20Gbps. (like what happened with USB Type-C* and USB 3.1->3.2)
*Yes, I'm well-aware USB-C is a just physical/interconnect standard. However, that's not how it was 'sold' to the market. The promise of "one connector to rule them all" turned into a quagmire of highly-varying implementations and poor accessory quality (IMHO: due, in large part to such 'loose' technical specifics.)

Not quite, as host devices can be 20 or 40 Gbps, this was enforced by a certain company in the USB-IF, whereas most companies only wanted the 40 Gbps standard. The 20 Gbps option might never happen. That said, I have a feeling we might see an implementation in phone SoCs at 20 Gbps, as it uses less power, gets less hot etc.
End devices can be 20 or 40 Gbps, but hubs, have to be 40 Gbps and also have to support all the various extras such as DP Alt Mode and so on.

LabRat 891Also, your mention of so few USB4 controllers on the market/ever to be made, makes me think USB4 as a whole is just about DoA (for consumer-enthusiasts).
Basically, it looks like its gonna get the 'firewire' treatment (having few, if any fully implemented integrations on the PC platform). Ending up largely relegated to 'professional media industry' and Apple.

Today there is only one, ASMedia. Obviously AMD has their own implementation in their mobile chips, but I have little to no insight into that host controller.
Intel and Apple are Thunderbolt 4, but Thunderbolt 4 is compatible with USB4, so shouldn't matter much, but Thunderbolt 4 is limited to 32 Gbps for data.
Considering that a lot of companies are working on USB4 peripheral chips, I doubt that is the case, as the final devices will be a lot cheaper than their equivalent Thunderbolt devices.

These are some of the key parts needed, but it seems like the lack of proper documentation is holding others back.
www.techpowerup.com/309492/realtek-demos-first-usb4-hub-controller-at-computex-2023
www.techpowerup.com/309667/vli-focuses-on-video-over-usb-c-at-computex

LabRat 891Addendum: I'm probably mostly jaded, since USB4 feels like we were supposed to have it 2 years ago. In fact, I can find rumblings in 2020 about USB4...
So, I'll admit to a sour attitude tinting my PoV; and I should really reserve judgement until AFTER ASM4242 sees full market-availability.
(I edited after reading specs on ASM4242, and it promises to be my every expectation and more.)

Well, I can tell you that ASMedia isn't overly pleased either, as they thought they were done and dusted in 2022, but ended up spending a year making a bunch of changes to pass the USB-IF certification. I can't go into too many details, as I don't want to put my friend there in an awkward position with the USB-IF.
www.techpowerup.com/309494/asmedias-delayed-usb4-host-controller-is-nearly-here

LabRat 891Edit 2:
Looks like there was some implementation on some 6000series APU option Mobile PCs. (at least after Firmware updates) Author also goes over early 'USB4 advertised' non-USB4 devices.

See above.

LabRat 891edit 3:
@8:33 in the video, he mentions that Microsoft Sticker-Certified Windows 11 laptops marketing USB4 port, must support PCIe tunneling.
Previously and by demonstration, 'not-actual-USB4' devices had me thinking otherwise.
Note: He does emphasize right afterwards how PCIe Tunneling is still an optional feature.

Host controllers and hubs have to support PCIe tunneling, end devices don't.

LabRat 891Thank You.
At least my sour feelings are not entirely w/o basis in reality.

As long as yields are good, and adoption wide, those Host and Device options from ASMedia are looking extremely attractive.

See more replies above. It's obviously about cost as well, but ASMedia's USB4 host controller is cheaper than Intel's Thunderbolt chips.

LabRat 891I'd love to slot-in an ASM4242-based PCIe Gen4x4 USB4 card into my X570
(even better if 4-ports using 2 interlinked via PCIe Switch ASM4242s, too :laugh:).

It might be possible. This card got a bigger heatsink for the retail launch.
www.techpowerup.com/309532/msi-first-motherboard-maker-to-offer-usb4-add-in-card-with-100-w-usb-pd

Just to have one, I picked up a USB4 cable in Taiwan this summer for $20, a lot cheaper than Thunderbolt cables and it can supposedly do Thunderbolt data as well.



Looks like the cable has a Cortex-M0 chip in it...
www.infineon.com/dgdl/Infineon-EZ-PD_CCG2_Datasheet_USB_Type-C_Port_Controller-DataSheet-v15_00-EN.pdf?fileId=8ac78c8c7d0d8da4017d0ecd9536480b

Asni"Transfer rates of up to 40 Gbps (5 GBytes/sec)"

3.8GB/s (3.938GB/s with 128b/130b encoding).
Hate fake marketing.

Btw, the 3.8GB/s effective bandwidth with Asmedia ASM2464PD chip (pci-ex x4 gen4 interface) has been tested on many products.
www.indiegogo.com/projects/zikedrive-world-s-first-and-fastest-usb4-ssd-drive#/
satechi.net/products/usb4-nvme-ssd-pro-enclosure
www.hypershop.com/products/hyperdrive-next-usb4-nvme-ssd-enclosure

TheLostSwedeIt might be possible. This card got a bigger heatsink for the retail launch.
www.techpowerup.com/309532/msi-first-motherboard-maker-to-offer-usb4-add-in-card-with-100-w-usb-pd

There is no pricing or release information just yet, but it will likely fall around $69+ range if MSI wants to remain competitive to the TB options out there, including its own TB4 solution. You’re also likely to see it launch sometime this year (hopefully, sooner than later so the company can move on to more feature-competitive options).

Retail Launch? Where?! I need it
(gives me an excuse to stop 'playing around with' Crossfire/AMD MGPU)

AsniBtw, the 3.8GB/s effective bandwidth with Asmedia ASM2464PD chip (pci-ex x4 gen4 interface) has been tested on many products.
www.indiegogo.com/projects/zikedrive-world-s-first-and-fastest-usb4-ssd-drive#/
satechi.net/products/usb4-nvme-ssd-pro-enclosure
www.hypershop.com/products/hyperdrive-next-usb4-nvme-ssd-enclosure

I saw it at Computex as well.
www.techpowerup.com/309494/asmedias-delayed-usb4-host-controller-is-nearly-here

Just spotted this on Twitter, apparently there will be 2 meter long USB4 cables, with a retimer chip in each end.

LabRat 891Retail Launch? Where?! I need it
(gives me an excuse to stop 'playing around with' Crossfire/AMD MGPU)

Should be out alongside the refreshed Z790 boards.