Pinging I.P Addresses

I am currently testing Windows 2000 Server at one of our networks. The unit does not have a connection to other PCs on the network. I tried to assign a manual I.P Address for the unit. It worked just fine but when I tried to ping it or check based on IPCONFIG it shows there is no LAN Card connected? Is it a requirement for Windows 2000 Server to have physical connection to other PCs just to simulate I.P Addressing and DNS Configuration? This worked just fined in Windows NT 4.0. Anyways to resolve this?