It seems the nForce boards are particularly problematic for audio cards.
First there were nForce4 issues with Sound Blaster X-Fi now there are nForce problems with Xonar, so keep that in mind when buying or advising.
More: nVidia knowledgebase
First there were nForce4 issues with Sound Blaster X-Fi now there are nForce problems with Xonar, so keep that in mind when buying or advising.
More: nVidia knowledgebase