ipconfig in 2000

I loaded windows 2000 on my laptop. then i docked it. it recogized the net adapter(3com) built into the dock. dhcp was default. went to dos prompt, typed in ipconfig/release, said was already release. then i typed in ipconfig/renew and it just hung there. closed the window. opened it up again, went thru same steps, and still hung. i have comcast cable internet, using dhcp. i know it works, cuz i am typing this in my desktop. by the way only have one cat5 cable, switched it between the desktop and the laptop. what am i missing? is it in the modem, or something in 2000? help would be greatly appreciated. laptop is inspiron 3800.

thank you,
John