I just built a new system with the below mobo and integrated NIC and I'm dual-booting with Windows XP.
GIGABYTE GA-EP45-UD3R and the LAN chipset is a Realtek 8111C.
In windows the NIC functions perfectly fine. However, in 8.10 Intrepid the NIC shows up, but is not showing link on the adapter. I reboot into Windows and it works just fine, so I know it's getting link from the switch. I tried to toggle the interface with the below commands to see if maybe it's getting stuck when the OS was coming up, but that didn't work either. What gives?
sudo ifdown eth0
sudo ifup eth0
I've been doing some more searching and the particular problem I have seems to be related to a Wake on LAN setting in Windows. I took care of that, but it's still not coming up with link. Next up is to pull the power plug, wait 15 seconds, then reboot and see if that fixes it.