13 Jul 12 10:24
A lot more info would be needed for someone to jump in and give an answer.
1) Is this a home or business computer? If business, contact IT and they will assign you one if Static. If you are IT, your bad for not documenting IPs.
2) Assuming you are running a Static scheme. Do you have to, and what are your address possibilities? Do you have other devices on the network? Can you go to a DHCP scheme?
3) What is the IP of the second card after installation? Are they on the same network or for different subnets?
4) What is the IP of your modem/router? That will be your gateway on normal schemes, if business, contact IT.
All the info you are going to need is the IP, subnet mask, gateway, and at least one DNS server. If the second NIC is on the same subnet, an ipconfig /all will show you the gateway, subnet mask, DNS servers, and its IP of which you can deduce a possible one for your first NIC.
Any other details greatly welcome. And as you have deduced, reapplying the image will take care of it but that seems a bit troublesome for a simple issue. If in XP, it is in this location of the registry HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces if it was previously Static.
Learning - A never ending quest for knowledge usually attained by being thrown in a situation and told to fix it NOW.