New to me the used Dell Optiplex 740 connection has been assigned a valid DHCP address however, using a new load of Ubuntu 12.04 the network menu shows the wired network in gray, yet it has allowed me to check the enable networking and assign the network name and password.

The good new net cable where connected to the computer lights only the yellow light.

Side note, the modem is about the 4th one as my rural telco uses some non standard protocol and it seems as though it's this one or nothing. I had a big problem getting the modem to work with direct TV as was then getting invalid invalid IP. addresses. Neither action tech or telco or direct tv was much help but I finally got it working by playing with security settings and port settings.

Other wise the Dell box passes all of the Dell diagnostics and am connected on the Internet with my iPad. Any suggestions would be appreciated. Thanks.