Intel X550-T2 very slow under Windows

[rekoil]

I have an Intel X550-T2 based NIC in my gaming PC, in Linux I can reach 10Gbit to both the internet and my NAS just fine, but in Windows 11 (it was the same under Windows 10 as well, just haven't had time to report it until now), the maximum speed I can reach is just shy of 3000Mbit.

I am connecting the X550-T2 using Cat6A to a MikroTik S+RJ10 SFP+ module in a Ubiquiti USW-Aggregation, also connected to this switch is my home server which has an X520-SR2 NIC, further down the stack is a Ubiquiti USW-Pro-24, and a UDM-Pro, with a 10Gbit internet uplink.

That's really all there is to it. I've seen others report similarly on different parts of the internet so I thought I'd open a discussion here to see if we can get to the bottom of it.

[Zigfreid_Intel]

Hello rekoil,

Thank you for posting on Intel Ethernet Communities. 

Can we ask first if you are using a discreet/add on NIC or are you using an embedded controller for your X550-T2?

If you are using a discreet NIC can we ask you to provide us a photo of the markings both front and back so we can validate your NIC. However if you are using the embedded controller of your mother board, please provide us the exact model of you board. 

If you have questions or other clarifications please let us know so we can help you further

Awaiting to hear from you soon, should there be no response from you, I’ll make sure to reach out after 3 business days. Thank you and have a nice day!

Best regards,

Zigfreid I.

Intel® Customer Support

[rekoil]

It's a discrete card, model is UCSC-PCIE-ID10GC, it's Cisco branded but it's an X550-T2 chip.

[Zigfreid_Intel]

Hello rekoil,

Thank you for advising us, also we'd like to set your expectation that for Original Equipment Manufacturer(OEM) Ethernet adapter, we have limited support and it would be best if you can also get in touch with the manufacturer for further support since they have customized drivers, firmware and software to enable or alter features on your card. They are in best position where you can seek assistance so you don’t lose features or customizations of the Ethernet adapter. But don't worry as we will still provide our best effort support to help you resolve the issue. 

Please try using one of our support articles for network adapters that are unable to Reach Gigabit Speed. 

https://www.intel.com/content/www/us/en/support/articles/000058667/ethernet-products/gigabit-ethernet-controllers-up-to-2-5gbe.html

If issue still persist after trying our recommended steps, please advise us so we can help you further. 

Awaiting to hear from you soon, should there be no response from you, I’ll make sure to reach out after 3 business days. Thank you and have a nice day!

Best regards,

Zigfreid I.

Intel® Customer Support

[rekoil]

Like I said, unchanged this machine (using this card) will easily do 10Gbit to the internet under Linux, so there's nothing wrong with the physical aspects here, it's just the Windows driver that's seemingly not performing well. Windows is selecting the Intel provided driver for the card so I'm hoping you can help me.

The support document you linked suggests to update firmware, I've been unable to locate the correct firmware for my card, I've opened a ticket on the Cisco support forums for that, but if Intel keeps a catalogue of OEM firmware I'd love it if you could send me the latest one along with the correct nvmupdate.cfg to be able to update using nvmupdatew64e.exe.

The rest of the guide I've followed, the card auto-negotiates 10Gbit link speed, I've turned off interrupt moderation, disabled offloading and flow control, to no effect, the card still struggles, in fact it's performing worse now, about 2.1Gbit when measuring with iperf3 to a 10Gbit capable VM on my network (yes, the full link to the VM is 10Gbit), though that's not necessarily due to any configuration changes, the speed kind of fluctuates between 1.3Gbit and 3Gbit (under Windows that is), maybe it's been higher once or twice, but rarely.

[Zigfreid_Intel]

Hello rekoil,

Thank you very much for providing us a detailed update and we do apologize if any of our recommended steps is unable help you solve your issue. Since you are using an OEM adapter from Cisco, we do have limited support on this and our NVV Firmware is only applicable to our retail adapters only. 

We will try to check what further recommendations we can advise you however we have no guarantees for a fix. Please provide us some time to check, would it be okay if we can provide an update between 2-3 business days? If you have a preferred date please advise us instead. Thank you and have a nice day!

Best regards,
Zigfreid I.
Intel® Customer Support

[rekoil]

That is completely acceptable, I won't be home for a few days anyway.

[Zigfreid_Intel]

Hello rekoil,

As per further checking, what we can only recommend you is to do clean driver installation and use the manufacturer's driver. 

Clean Driver Installation Guide for Intel® Ethernet Connections

https://www.intel.com/content/www/us/en/support/articles/000058304/ethernet-products.html

If the issue is still persistent, please continue to coordinate with your OEM (Cisco) since they control the driver, firmware and product quality so that you don't lose features or customizations of the Ethernet adapter. 

If you have questions or other clarifications please let us know so we can help you further.

Awaiting to hear from you soon, should there be no response from you, I’ll make sure to reach out after 3 business days. Thank you and have a nice day!

Best regards,

Zigfreid I.

Intel® Customer Support

[Zigfreid_Intel]

Hello rekoil,

Good day! We hope that you are having a great one so far.

We'd like to know if you have any other questions or clarifications please let us know so we would know if we can close the thread.

Hoping to hear from you soon.

We will wait for your reply within 3 business days in case we don't hear from you, we will proceed closing this request.

Best regards,

Zigfreid I.

Intel® Customer Support

[Zigfreid_Intel]

Hello rekoil,

Good day! We hope that you are having a great one so far.

Please be informed that we will now close this request since we haven't received any response from our previous follow ups. Just feel free to post a new question if you have any other inquiry in the future as this thread will no longer be monitored.

Best regards,

Zigfreid I.

Intel® Customer Support