go to device manager, remove all devices remotely related to multimedia, then reboot. Works for me, maybe not so much you.
Sounds good. And be sure there are not any yellow flags in device manager for devices without drivers. If nothing helps to get the OS to detect the card then try installing a copy of XP if you have one. If XP doesn't detect it either you might try updating your BIOS and if none of that works you may have a bad sound card chip.