Heh, i just installed an Asus Xonar DX and it has made my DT770's sound so much better than with my Audigy 4!Got these yesterday.
Luckily just managed to miss a price rise headphones were only £57.95, soundcard was £59.99. Sounding great so far though!
Didn't even think i would see such a huge difference. When i got the Audigy 4 it was a big step up from onboard, but this seems like an even bigger step again. Awesome!