You can plug the Asgard directly into the line output jack on your sound card...The Asgard even comes with the right adapter cable to do that. Your sound quality will improve a bunch when you replace the sound card in your PC with an external DAC, but take your time and one step at a time.
You could even bag the Asgard for now and get a NuForce μDAC-2 for about $120. That will give you a decent external DAC and headphone amp all powered by the USB bus. The speakers can plug into the line outs on the back of the new DAC and the headphones into the jack on the front. You can upgrade the headphone amp separately at a later time. The NuForce will work well with your current cans.









