Sorry, forgot the sound card thing.
As far as I know, the interface you mention is just an interface/usb converter. I'm pretty sure you still need a sound card but I'll defer to somebody else on this one cause I'm not as familiar with PC's as I am with Macs.
As far as I know, PC's don't come with a built in sound card like Macs do.
With my mac for instance, all I do is take the output from the mixer and plug it into the RCA audio inputs at the back of the computer. No sound card required. For midi, I use a translator through the modem port.