Hey guys new here. I also like to play xbc. Here is how I set mine up, very simple. I have a motorola surfboard for cable internet. On the back there are 2 ways to connect to your computer either trhough usb or through nic. The way I did it was to connect my pc via usb and connect my xbox directly into the back of the cable modem. Works perfectly. Here is a link that might help otherwise.
http://www.xbchelp.com/network/
Lets get a game going somtime.
iFaQ
