I have been reading many posts lately trying to sort out all the "need to know stuff" before installing a two computer network. I have 7 IP Addresses (free) available) and need to know under which conditions that I need a network card that goes with the cable modem and another that goes with the network.
It might help if I also knew under which conditions I would not need a second card.
You need two network cards if you want to share your cable modem onto your network using ICS or a proxy server or something. You usually do that only if your ISP gives you a single IP address. When you say you have 7 free, I'm assuming you mean that your cable company gives you seven. If that is the case, then you can connect your cable modem directly to a hub or switch, and have your computers on that hub (or switch) as well. If you don't have a hub and don't want to buy one, you can still use two network cards to do the same thing, but it's a less-than-ideal setup, especially considering the computer with two NICs would need to be on almost all the time.
Running a PIII 800e on an AOpen AX34 Pro II with 256 MB of some WICKED PHAT GENERIC PC133 Cas3 RAM
If you have multiple ip addresses available, I wouldnt go the route of putting multiple nics into a single computer. Usually, you need to do this when sharing a single ip address amongst multiple computers (you have a computer connected to the cable modem and the second network card shares the connection to the rest of the network). However, you have multiple addresses available to you. In this case I would connect a hub or switch to the modem. Then you only need a single card in each computer that you need to connect to the internet (just connect them to the hub/switch).
You will want to have a firewall on each of your computers in this case (as they will all be directly connected to the internet). How did you get these addresses free?