I'd avoid any of the low-price Asus Xonar cards. After having just purchased the DS1, I was exceedingly disappointed. I've got a fairly discerning ear, and if anything, it sounded worse than my on-board sound. Now, I have an enthusiast class motherboard, so the Realtek codec used is no slouch, but it certainly isn't perfect either. In terms of general sound quality, if you're simply looking to improve your 2.1 setup, then I'd recommend one of Creatives older X-Fi generation of cards. They can be had for reasonable prices and all offer fairly stellar sound quality. For just under $200 you could land yourself one of Creatives new Core3D cards and a nice set of 5.1 speakers or a 5.1 headset. 5.1 makes a huge difference in games in my opinion and adds a whole new dimensionality to First Person Shooters specifically. I've got a few specific memories of it getting me points I wouldn't have gotten otherwise.