Sounds like you may have a bum motherboard man, or a mis-configured BIOS.
As for Vista only, you should check the CL website and download the drivers from there. Never use the supplied drivers that come on CD. They are buggy and out of date by the time you get them.
As for running multiple soundcards, that shouldn't be a problem either and it is 99% chance not causing your problems. XP and Vista both are designed to handle multiple audio devices.
Give me some more details if you don't mind. I might have a thought or two with more information.
-S
__________________
 
|