Either use the latest from the ASUS site for your board, or find the chipset on the manufacturer's website. I prefer to not use the installers and just point devmgmt.msc to the latest driver.

The ASUS drivers can be found here: http://www.asus.com/us/Motherboards/MAXIMUS_III_FORMULA/HelpDesk_Download/

The manufacture's driver can possibly be found at: http://support.creative.com/welcome.aspx

Although, I'm betting this device was special made for the motherboard and thus the latest drivers are put on ASUS's site from creative. I hope this helps!