I've been using a Mini-ITX PC with integrated sound for a while and it's just not up to the standard of my previous Creative X-Fi soundcard when used with my Audio Technica AD700 headphones. So, I'm pondering ways to improve it. I don't have a slot for an expansion card, but I do have empty space where the case could fit a few 2.5" drives as well as a free internal USB2 header so I'm considering fitting a small USB DAC inside. Total free space is around 6cm x 11cm x 12cm. I'm just wondering what my options are. There is stuff from the AV world like the Dacmagic XS and Dragonfly Black but you get the impression they're pretty high margin products. Are any of the gaming world products from the likes of Creative or Asus better value? Or better suited to game audio? What about stuff for the mobile market, Fiio etc. Big competitive market, but does the requirement to minimise power draw and the extra expense of a battery make it a suboptimal option for big headphones on a computer? Or should I be looking at a different option entirely?