I would suggest going to the manufacturers web site and look thru the FAQ's and tech support area for a solution. These cards are very complicated and some times the slightest change in the system can knock them screwy. I would also check out Microsoft tech net for possible solutions.
http://www.microsoft.com/technet/prodtechnol/winxppro/default.mspx
http://www.microsoft.com/technet/prodtechnol/winxppro/default.mspx