Don't forget that digital isn't better than analog. You want the best piece of equipment to do the decoding, so only use the digital output of your sound card if you feel that your new equipment can decode it better than your sound card can. I highly doubt any of the computer speaker systems have processing close to the caliber of the higher end sound cards. Almost all (if not all) of them have cheap IC's stuffed inside a "control module" with a volume knob. If you get a home receiver or integrated amplifier though, I would most definitely use the digital out. If you don't get a home unit, I'd let the sound card do the processing if you have a good one.