Why would you need a digital I/O card?
The SBLive! 5.1 card has 2 channel or AC-3 digital out in either creative mini-DIN or SPDIF RCA format.
It has 4 or 5.1 channel digital out in creative mini-DIN format
It has 2, 4 or 5.1 channel analog out in 3x3.5mm stereo minis.
I'm not sure what the connections on those speakers are like, the SBLive! 5.1 should have anything you need to connect with, unless they are optical. You just need the right cabling/connectors.