i need help.cant play with 2 cpu`s with one cable modem

[[BiA] SlyFi]

Here it is ,I have 4 cpu`s in my house, and i can not connect to any sever with two or more cpu`s only one computer...If i im on" HP " sever my other cpu`s will not even see the sever.. I have a Linksys 4 hub router system with a cable modem..How do i fix this crap so me and my friends can all play at my house and be on the same sever....Any Help would be nice guys... Steve

[DragOn]

Use same name for networking/Computer for every single computer you are trying to connected to...