please help me! ...

I am running a dual boot system with linux (mandriva LE 2005) and windows xp. I am connecterd to a server which all the pc's connect to and i use a router to connect to the internet.

in windows xp my network runs fine and i can connect fine to the different PC's and the net.
in mandriva i setup the network with the same settings from xp (same ip,DNS,gateway etc..) but i cannot use the internet or see any other pc's !!

PLEASE HELP !!

(if u need any more info just ask!)