Vortez.co.uk posted a review on the ASUS Xonar DS 7.1 PCI Sound Card

For a long time, Creative dominated the hardware sound market and the launch of the X-Fi series of cards placed them firmly at the top of the game with features such as EAX 5.0, X-RAM and other 3D sound emulation software. Gamers looking for a more immersive experience had only one choice and that was Creative. However with the introduction of Windows Vista and growing frustration towards Creative on the basis of their lack of support, a gap opened up in the market which was immediately filled by the ASUS Xonar. Vista saw DirectSound being deprecated so as to introduce a re-written audio stack based on Universal Audio Architecture. As a result, creative's main advantage EAX 5.0 was effectively gone on older DirectSound based game since there was no longer direct communication from DirectSound to the hardware.

ASUS Xonar DS 7.1 PCI Sound Card Review