any board with the vt8237 southbridge and the vt1616 codec (it needs the vt1616 codec to take full advantage of the via vinyl envy stuff built into the southbridge)
i know the asus kt600 board doesn't have the vt1616 codec
i know the soltek kt600 and aopen kt600 boards both do have the vt1616 codec
and i really dont know about any other boards
a nice review on the anandtech main page a few months back of the soltek board
http://www.anandtech.com/mb/showdoc.html?i=1852&p=2 (scroll down half way and you can read about the audio on the board)
**copy/paste** from the anandtech review linked above
In other words, the VT1616 codec provides better sound than an MCP-T powered nForce2 motherboard unless you make use of a SPDIF-out port and have speakers with a receiver.
last time i checked it seems like they were around $70 at newegg