Ethernet Disconnecting on Z490 Asus Motherboard using 3 different Ethernet Interfaces

[Tim_S]

I have an Asus ROG Maximus XII Hero (WiFi) motherboard that keeps having ethernet disconnections. The board has two built-in ethernet controllers, the Marvell AQC111C 5GbE and the Intel i219-V. I wanted to use the 5GbE connector, since I have 2.5 GbE fiber ethernet service, but I kept having intermittent ethernet disconnections. I RMAd the motherboard, and the replacement still has the disconnect issue. 

I then tried the i219-V. I still had the problems with the ethernet disconnecting. Moreover, I could not get the download or upload speeds above 0.1 GbE.

So I gave up on the two installed ethernet controllers and installed an Intel X550-T2 PCIe controller. Now at least I'm getting nearly 2.5 GbE upload and download most of the time, but I still keep having intermittent ethernet disconnections!  

I'm really at my wit's end here. I have two other computers connected to the same router/switch, and those connections are rock-solid. Never a disconnect. But this Z490 board just cannot keep a stable ethernet connection. What else can I try, short of tossing this whole computer in the trash and buying a Mac? 

I'm running Windows 11, build 21H2, with driver version 4.1.248.0 for the X550-T2. 

[Mike_Intel]

Hello Tim_S,

Thank you for posting in Intel Ethernet Communities. 

For us to further check the issue, please provide the following details.

1. Are you also having this issue on a different OS or you just tried it on Windows 11?
2. Can you share the link of the driver that you are using?
3. Did you also tried different cables for this network card?

If you have questions, please let us know. In case we do not hear from you, we will make a follow up after 3 workings days. Thank you.

Best regards,

Michael L.

Intel® Customer Support

[Mike_Intel]

Hello Tim_S,

I hope you're having a wonderful day. I am just making a follow up on the information that we requested for us to further assist you. We will wait for your reply.

If you have questions, please let us know. In case we do not hear from you, we will make a follow up after 3 workings days. Thank you.

Best regards,

Michael L.

Intel® Customer Support

[Tim_S]

Hi Michael, 

I tried a different cable, and it seems to have solved the problem! I had already replaced the cable with a new Cat7 ethernet cable, and still had the disconnect issue. But I've now replaced the Cat7 cable with a new Cat8 cable, and the ethernet connection is finally stable. However, the upload speed is inconsistent, ranging from about 155 Mbps to 2100 Mbps, while the download speed is consistently around 2400 Mbps. Both should be the same under my fiber service. Any thoughts as to why the upload speed is so inconsistent? 

Thanks for your help. 

Tim 

[Mike_Intel]

Hello Tim_S,

The network card in this case is onboard and it is considered as an OEM unit. It seems that the network card has a compatibility issue with the LAN cables. We recommend to contact Asus for further assistance, they may have custom driver, software and firmware for this network card. You can also clarify with them the recommended/compatible LAN cable.

If you have questions, please let us know. In case we do not hear from you, we will make a follow up after 3 workings days. Thank you.

Best regards,

Michael L.

Intel® Customer Support

[Mike_Intel]

Hello Tim_S,

I hope you're having a wonderful day. I am just checking and hoping that you are now talking with Asus for further assistance since they are the best team who can further assist you.

If you have questions, please let us know. In case we do not hear from you, we will make a follow up after 3 workings days. Thank you.

Best regards,

Michael L.

Intel® Customer Support

[Mike_Intel]

Hello Tim_S,

I hope this message finds you well. I am just sending another follow up to check and hoping that you are now talking to Asus regarding the issue since they are the best team who can assist you. Since we have not heard back from you, I need to close this inquiry. 

If you need any additional information, please submit a new question as this thread will no longer be monitored.

Thank you and stay safe.

Best regards,

Michael L.

Intel® Customer Support