Auto-negotiation causing disconnects

[MarkGDK]

Hello,

I've just built a new PC with an X399 MEG Creation motherboard from MSI. The motherboard has 2 x Intel I211AT Gigabit LAN controllers.

The problem is that the PC is constantly connecting/disconnecting when the "Speed/Duplex" setting is on "Auto Negotiation". When i set manual values the problem doesn't encounter so far i know. It happens on both ethernet ports.

I've tried completely removing the drivers and reinstalling them with the latest, but it didn't have any effect. I also turned off the energy power saving on the adapters. When i connect my laptop to the same ethernet cable the problem doesn't occur. What could be causing this?

[MarkGDK]

I have just connected the computer to an gigabit ethernet port on the router, and auto-negotiation is now working. So it appears auto-negotiation is not working properly when connected to a 100Mbs port. The strange thing is when i connect another PC to a 100Mbs port it is just working fine. Is this supposed to be with those intel controllers?

[Caguicla_Intel]

Hello MarkGDK,

Thank you for posting in Intel Ethernet Communities. 

The settings configured on the Speed/Duplex should be set the same way on your router. If you plan to use Auto negotiation, it should be set on router as well as the adapter and both should support gigabit speed.

Let us know if you have additional questions and clarifications.

Awaiting to your response.

Should there be no reply, we will make sure to reach out after 3 business days . 

Best regards,

Crisselle C

Intel® Customer Support

[Caguicla_Intel]

Hello MarkGDK,

Good day!

We'd like to check if you have additional questions and clarifications on this matter. If you do, please let us know for us to further assist you.

Hoping to hear from you soon.

Should there be no response, we will follow up after 3 business days. 

Best regards,

Crisselle C

Intel® Customer Support

[Caguicla_Intel]

Hello MarkGDK,

How are you doing today?

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 may have any other inquiry in the future.

Best regards,

Crisselle C

Intel® Customer Support