1: never heard of those speakers or how they sound, won't comment on that.
2: I think the card you have has better specs than the USB version.
3: As long as you use the Analog outputs of your audio card (any card) it will work with the Edifier, as it uses 6 RCA inputs (no chance of drivers or software failing)
2- the problem is that I don't have room for the " Internal" sound card when i upgrade
so you are saying that if i bought the USB version it would be a Downgrade not an Upgrade ?