Realtek Gaming 2.5GbE Family Controller capped at 100 Mbps
Realtek Gaming 2.5GbE Family Controller capped at 100 Mbps
Hello, after replacing your motherboard, you're facing issues with your network adapter. It sometimes freezes at 1GB speed and caps itself at 100 Mbps. You mentioned updating drivers and adjusting the speed settings. Could you clarify if there are any other symptoms or steps you've tried?
Adjust the connection speed to 1000mbps and enable full duplex via Device Manager. Those Realtek chips seem to struggle with auto-detection, so if you notice interruptions, the cable might be unreliable.
If it doesn't turn out to be the cable, I've experienced several Realtek onboard NICs failing in this way. They consistently lock at 100mbps regardless of the operating system, router, or cable used. Likely it's not the cable, but if that's the case, you have a few alternatives. If you still have a warranty, returning it for repair (RMA) is an option. Another choice would be to purchase a replacement NIC—either USB or PCI-E—especially if you don't want to remain offline. These solutions apply only when the problem isn't with the cable, router, or switch. Cheers.