xbox to pc connection problems

[frequency]

ok....my pc is connected to my dsl router and my xbox is connected to my pc via a ethernet card and a rj 45 cable sense my dsl router has for only one opening in the back. but i dont see any green blinking on the ethernet card to confirm any activity going on. my xbox has been chipped and all of the drivers for the ethernet card are properly installed and the device says thats its working properly. so how do i go about to fix this problem? plus i dont know if my router has giving my xbox a ip address. any thoughts?