two computers one router

[brainspilla]

both winxp when I log on to regnum everything is fine same for her but if we both try to play at the same time our internet connection goes down and we have to reset the modem. It's broadband.

[Wingerit]

i have 3 computers and all of them can play at once .
but I had an older router that use to do the same thing .
when more the one computer logged on it would cause the router to lock up and had to reset router to work again.
what kind of router do you have? see if there is a router firmware fix for it .