this might apply to you , it dose for me . I have a old 2000 - 2001 network card and the ONLY and i do mean only way i have been able to get it to work in fedora 4,5,6,7,8,9 was to install with ipv6 disabled during the install .
Once fedora was installed there was no way to get the card to work if ipv6 was enabled during the install .
you might have to reinstall and disable ipv6 support with the installer .
I went into network configuration and activated, but it is still showing like the cable is unplugged. It was working previously but ceased after a reboot.
check in the services and see if you have " network" AND "networkManager "
both turned on
if both are on they conflict with each other.
if you are using wireless leave "networkManager" on
if NO wireless then leave "network" on