I had this to on my computer with a gigabyte motherboard, do a google search for some advice.
In the end I deleted the Realtek drivers and programme for the sound card and the system then installed all the drivers but not the programme to support the card, but works. I wouldn't suggest you do this.
As time has passed now some better information than when I made the delete decision.
http://www.webmasterworld.com/micros...os/3301956.htm
http://support.microsoft.com/kb/925902