The PCI modem needs to go and it gets replaced with an ADSL modem/router (A router is NOT a modem, but a modem/router is!) True with a USB modem in most cases, but particularly true for your PCI modem. After all, there is no connection between a network host and its clients other than a LAN cable or wifi link so it is phyiscally impossible to send an internet connection UP to a host FROM a client. Internet connections can only come from the host to the clients. Hence even ad-hoc networks have a host. If this is a desktop PC, use a PCI card, making certain that it supports WPA or WPA2 encryption.