The Turtle Beach Santa Cruz card that came with my Dell does NOT do 5.1 digital. It does support up to 6 speakers in analog mode (which sounds really good to me!). It has what they call a Virsajack. Besides the normal jacs for front, and rear speakers, it can be configured for speakers 5/6, or headphones, or "digital". It can do "virtual" 4.1 digital, but it does NOT have a SPDIF jack. Maybe that's what the virsajack is for? Check out thier web page for details.