Thunderbolt P2P / TB4 - 1.5GB/s

[sfx2000]

At the end of the day - $60 cables and $200 10gb ethernet adapters - this is the cost of doing Thunderbolt

It's always been that way - even going back to Firewire 400/800 and USB there...

There isn't really a cheap way out with TB3/4- and most folks that use Thunderbolt, it's their business, not a hobby...

I've been thinking about this...

@Tech Junky - rather that call it TB3/4, consider just doing USB4 - In some ways this casts a wider net, both on peripherals and host adapters...

The Thunderbolt community and market actually is pretty small compared to the USB world - much like Firewire and USB back in the day...

Find the value in USB...

Windows will always do better USB than Thunderbolt as USB is native in the Windows stack...

 

[Tech Junky]

@sfx2000

Name doesn't matter if you want to just call it USBC / 40G but, form the technical aspect of protocols wording matters. Spec's don't use the terms interchangeably because they aren't. USB4 has a floor of 20G not 40G for certification.

Picked up an overstock TB cable though for under $25 @ 9 FT. Still need to test it but, have something else showing up tomorrow that necessitates opening the case and need to swap some slots anyway so maybe I'll test the cable while I'm messing with things. Either way so far the speeds are better than a 10GE would be. It would just be nice if they would hit higher.

I put the TB card into a x1 electrical slot and in the logs it's spitting out higher bandwidth messages if put into a x4 slot. Not really an issue though as I don't use it daily for anything. I'll have to test it in the x1 to see if it affects the speed of P2P or not.

[    0.404993] pci 0000:08:00.0: 7.876 Gb/s available PCIe bandwidth, limited by 8.0 GT/s PCIe x1 link at 0000:06:02.0 (capable of 31.504 Gb/s with 8.0 GT/s PCIe x4 link)
[    0.405276] pci 0000:09:00.0: 7.876 Gb/s available PCIe bandwidth, limited by 8.0 GT/s PCIe x1 link at 0000:06:03.0 (capable of 31.504 Gb/s with 8.0 GT/s PCIe x4 link)
[    0.405593] pci 0000:0b:00.0: 7.876 Gb/s available PCIe bandwidth, limited by 8.0 GT/s PCIe x1 link at 0000:06:0a.0 (capable of 31.504 Gb/s with 8.0 GT/s PCIe x4 link)
[    0.405874] pci 0000:0c:00.0: 7.876 Gb/s available PCIe bandwidth, limited by 8.0 GT/s PCIe x1 link at 0000:06:0b.0 (capable of 31.504 Gb/s with 8.0 GT/s PCIe x4 link)
[    0.412611] pci 0000:4f:00.0: 7.876 Gb/s available PCIe bandwidth, limited by 8.0 GT/s PCIe x1 link at 0000:4e:00.0 (capable of 31.504 Gb/s with 8.0 GT/s PCIe x4 link)
[    0.415522] pci 0000:51:00.0: 7.876 Gb/s available PCIe bandwidth, limited by 8.0 GT/s PCIe x1 link at 0000:4e:00.0 (capable of 8.000 Gb/s with 2.5 GT/s PCIe x4 link)
[    0.416101] pci 0000:53:00.0: 7.876 Gb/s available PCIe bandwidth, limited by 8.0 GT/s PCIe x1 link at 0000:4e:00.0 (capable of 31.504 Gb/s with 8.0 GT/s PCIe x4 link)

This also points to the speed limitation of TB3/4 w/ the 31.xgb/s part of the message. That's obviously not 40gbps and syncs up with my max speed results using the TB enclosure.

Besides all of this there's no native USB4 controller out on the market yet. ASM has one in the works now for over 2 years since breaking cover but, it still hasn't hit the market but, smells like it will by the EOY hopefully. This will unlock Gen4 speeds ss well bumping the PCIE data use to ~3.8GB/s but, the trickery continues w/ TB 5 coming next year. The whole swapping of lanes from 80 >> 120 for displays means there's probably a reduction in data only speeds or Intel will just keep the speeds on par w/ G4 like ASM. The problem with these new protocols to overcome will be proper labeling on cards / cables / devices.

 

[sfx2000]

Name doesn't matter if you want to just call it USBC / 40G but, form the technical aspect of protocols wording matters. Spec's don't use the terms interchangeably because they aren't. USB4 has a floor of 20G not 40G for certification.

Please do not get me wrong - TB vs USB is an ongoing argument that transcends the application layer of the protocol stack - we're talking business/political/religion - TB will always be TB, and USB will always be USB.

USB4 is pretty awesome - and it will always be more "universal" than TB, and it has backwards compat with the rest of the USB world...

I'm sure you can plug a mouse/keyboard/thumbdrive into a USB4 port, and it should just work - that same device won't work in a TB1/2/3 port as they are two different connectivity stacks from the physical layer upwards...

USB4 and TB4 have similar characteristics, and there's limited portability across them - and UBS4 will always win the value discussion...

 

[Tech Junky]

USB4 only exists in theory right now though since there are no native USB4 controllers that aren't just built on top of TB3.

There might be some mobo's that have one or two ports that are technically USB4 but they're 20G ports and not going to be able to hit 40G.

If they do 40G they're using the JHL8540 which is TB.

 

[L&LD]

TB1/2/3?

Old news.

USB 4 v2 (see video below)

Intel Introduces Thunderbolt 5 Connectivity Standard

The industry-leading connectivity solution will provide up to three times more bandwidth compared with Thunderbolt 4.

www.intel.com

 

[sfx2000]

This was an interesting read...

USB-C head-to-head comparison

The reign of the Lightning cable is over, and the USB-C era has begun — leaving us wondering what sets one charger apart from another. We do a teardown of Apple's Thunderbolt 4 and its competitors.

www.lumafield.com

 

[Tech Junky]

@sfx2000

More of a sales pitch for their X-ray scanner. Proof is in the performance on the system it's being used with. Price isn't everything when it comes to performance but, if you can get a $24 cable to work the same as the Apple $150 option then so be it.

There are different categories of USB cables though from 480 / high voltage / no data or 40g / high voltage PD 3.1.

I always aim for the highest V/A/Gbps option at a decent price though because I tend to use them for different things other than data only. There isn't any 240W TB option yet as I'm guessing they're needing certification still for TB5 specs which roll in the higher PD specs.

This is the new cable I picked up -

https://www.amazon.com/dp/B0B2LXZ758

Still selling for $25 but w/o a coupon now.

I haven't done a speed test with it yet but, I have some faith it will do 20G just fine like the others I tested for twice the price. I take the trust but verify approach when it comes to tech items. Make sure you're ready and able to test things within the return period because dealing with an RMA is 10x worse in terms of time it takes to resolve the issue and sometimes RMAs don't even do that if they just send the item back in the same condition.

 

[sfx2000]

FWIW - I find your explorations fascinating...

Keep up the good work, and more importantly, keep posting...

 

[Tech Junky]

keep posting.

That shouldn't be an issue.

 

[sfx2000]

This looks interesting...

https://www.amazon.com/dp/B0B13XC75J/?tag=snbforums-20

BIt spendy, and it's a case only, one still needs a M2 drive to drop in...