Can you post the make / model of your puter and the network card? May help someone troubleshoot.
The network card will often light up if it is powered, but doesn't necessarily mean that it's at home.
If the BOIS stuff don't work consider the following. Remove the card and reboot the PC without it, into safe mode (press F8 during the bootup process before the windows logos start to appear but after the intial BOIS memory checks come up). Now you can look at network connnections from control panel, and device manager and ensure all traces of your USB connection have gone, and also delete anything loaded by your new network card, including any programs autoloaded from an install CD (Add/Remove software)
Swithc off the PC. Refit the card, in a different PCI slot. Boot up the PC normally. Ideally the card will be plug and play and windows will give messages of new hardware. If not load the install CD, and any install software. Reboot the PC normally may then trigger an autodetect of the card. Alternatively go back into network connections and or My computer > hardware > Device Manager and see what's there to load the drivers from the install CD.
As a last resort, you could try getting updated drivers from the Web. Most manufacturer's have web sites you can donwload from
Good luck
