How do I properly support two network cards in one Windows 7 PC?

How do I properly support two network cards in one Windows 7 PC?

I've upgraded from Vista to Windows 7. On Vista I used to run one network card (Intel 82566DC -2 Gigabit) for my internet which was connected to a Dovado USB mobile broadband router connected to a 3G modem. The IP setup on the card is set on DHCP. The second card (3com Ethernet link) was used to connect to our town's local WUG (wireless user group) and all worked fine.