first thing check if the maudio driver supports asio - AFAIK it did in xp - check for vista also. Also if there is no asio support simply use asio4all. And if you have flac - then download CPlay. (for more details download CPlay first).
second congrats on the new card. You will notice atleast a 10-20% improvement over the onboard sound chips and the sound staging and clarity will be great.
M-Audio driver-installer by default install a driver called "M-Audio Delta ASIO" which i could select as output device in foobar2000. I could experience almost 40% improvement in sound quality