My ethernet connection is not working but it is detected by my computer

view story

http://askubuntu.com – I'm setting up an old computer with ubuntu server 12.04. I wiped the drive and went through the installation fine but afterwards the ethernet would not work. It's physically connected to the router and the card is recognized by lspci(SiS 900) but it won't connect at all. I've plugged in and installed the drivers for a wifi adapter and it's worked with the same router. Just so you know I've turned it on and off plenty of times. Any help would be appreciated. (HowTos)