The Vista Driver for Realtek AC'97 Audio is here (at this point dated
2006/11/16):
http://www.realtek.com.tw/downloads...=23&Level=4&Conn=3&DownTypeID=3&GetDown=false
You should not have any problems with your sound when you upgrade, since the
driver exists. If I understand your question, updating your current
(non-Vista) Windows OS driver won't really help anything, other than
possibly your current OS (for which you must install the appropriate
driver). You can't install a Vista driver, though, until you have upgraded
to Vista first. The driver for, say, a Windows XP operating system, won't
be used by Vista. In other words, the Upgrade Advisor is only cautioning
you to find out whether or not a Vista driver will be available for your
device, and not telling you to install one now, before you upgrade.
Dean