Failed network connections

I have a Dell OptiPlex GX1, with a network adapter right
on the motherboard. The card shows up in my System
browser, and under the networking tab. The connector
lights up when it's plugged into my network. I'm logged
on to my computer. The TCP/IP protocall is bound to the
card. However, ipconfig/winipcfg doesn't recognize
anything but a PPP connection, which is my modem, and I
can't even get the computer to see itself in network
neighborhood. I've already checked if my computer was
automatically logging on, but that wasn't the problem.
Might I be overlooking something quite simple?