Vista - Connectivity issues

I am running a XP / Vista setup in a dual boot configuration. I am on
broadband using a linksys cable modem and a Linksys router. Prior to
installing Vista I had no issues with XP and connectivity. However since I
have installed Vista, I no longer have any connectivity on the XP side. When
I boot into Vista I have no problems at all. I have been through everything
I can think of, to no avail. I have taken and made sure that the settings
are the same on both OS's, as I saw that might have been an issue on another
posting. Without deleting Vista is there a setting that will get my XP back
out on to the net? I have tried to undo the router and plug directly into
the cable modem but on XP there still is no connectivity, which leads me to
believe that there is a setting somewhere that I am missing. Any help would
be greatly appreciated.