Achieving the best sound quality possible

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I have a Asus Xonar DGX soundcard.
Could i add something with my soundcard for better audio quality with my monitors?

 

[americanaudiophile]

You can't really add anything to your soundcard but you could bypass it with a USB DAC. For music it would be better but how much you would hear depends on how good your monitors are.
At the entry level check these out
http://www.schiit.com/products