We have a Dell Precision with integrated NIC that's randomly losing network connection. Both connection to our Windows 2003 server and internet drop. When I unplug a cable from either the wall to the computer or the connection cable in the server room, the connection returns. (No restart of the computer is needed) This happens several times a day.
I've tried renewing the IP address and that doesn't work. The only thing that jumps it back is unplugging a cable.