USB4 PCIE GEN4 Card bandwidth issue

[kalo86]

Dear Community,

I bought the USB4 PCIE GEN4 Card and installed in my PC with the motherboard ROG STRIX Z790-E WIFI II.
I installed the USB4 card on the lower slot of the motherboard and I see that the USB4 host is correctly detected by Windows 11 Professional.

The problem is that I don't achieve the theoretical bandwidth of 40Gbps, even if I connect the NVMe USB4 enclosure to the USB4 plug:

Can you please help me? Thank you.

[Arcadia]

USB4 - Wikipedia Gen2x2 appears to me is your Ugreen Storage device, the specifications describe the difference between 2x2 and 3x1 to be the number of wires. May i suggest a cable issue?

If windows negotiated the wrong generation, perhaps a firmware update could help.

mind you (if you hadn't already), 2x2 is maximum of 40Gbps one way. (i've also been reading about interference playing some issues.

[kalo86]

At the end I managed to achieve the full theoretical 40Gbps bandwidth.
Honestly I don't have any clue on what fixed the issue, but I can list what I did for future memory or for user who may face the same problem:

1. Install the latest ASUS USB4 PCIE firmware: this is quite confusing because Asus released several version and the upload date is always the same. Furthermore, to make things more complicated, more recent firmware's have a lower index number! Thanks Asus to be messy. My suggestion is to read carefully in the firmware description and pick the corresponding one which is matching with the chipset generation (in my case Intel Z790).

2. Go to BIOS and disable Thunderbolt tunnelling. Reboot. Enter BIOS again and enable Thunderbolt tunnelling.

3. Flash the most recent firmware for your SSD USB4 enclosure.

After doing these steps, I achieve the 40Gbps and the read & write speed on a WD SSD PCIe Gen4 is around 3700MB/s which is outstanding.

I hope it helps! Best regards, kalo86

[Arcadia]

I'm very glad you solved your problem. Personally i don't think tunnelling would be relevant, sounds like an old school northbridge topology, which in this case would be completely irrelevant, also just googled it...doesn't make sense. (however my type-c ports currently aren't handing-off properly thanks to IME, i'm thinking usb will be the main antagonist in the next "flash" movie)

but firmware updates from my take on things appeared to complete the puzzle. very happy to hear.

[kalo86]

Thanks for your comment. Honestly, the Ugreen enclosure is already born as USB4 with 40Gbps capability. Many users around the world are using it and it works in many cases as it should be out of the box. In my case, I think that the old firmware of the USB4 pcie was wrong and I strongly believe it because the performance in USB 3.2 was even better than the USB4. That was my driving alarm suggesting to flash another firmware on the USB4 card. Anyway, it was a journey and I am quite satisfied for the result. It's just sad that these steps are very risky and not accessible to anyone. I was tempted to return the expansion USB4 card, the Ugreen enclosure and the additional SSD. Basically around 300,00€ of hardware not correctly usable. 

[Arcadia]

in programming there is something called off by one error, kind of like your versioning index joke. my brother always use to love arguing whom was better in the world of IT, hardware or software haha

in all honesty, quality control rules over all, benevolence should always be part of any workflow.... but we all have jobs to do, so GO TEAM EFFORT

[Arcadia]

That being said, we all have enough stress in our lives, from at least 50 documented rationales, in my case with my usb-c it's long term goals verse short term problem solving. From you statement it was partially a good financial standpoint (plus other unstated).

QC does need a little attention.