Unfortunately, i have not been able to find a solution to this. It is obvious that this is a quite persistent problem because the web is loaded with threads on this. I recently did a clean install of Win7 x86 ultimate on my girlfriends old Gateway MX6436 Notebook (2005'ish). Even though i am an running Win7 on only 512mb of RAM, so far it has worked flawlessly.....except.... the sound card. ''Realtek AC '97" "This driver cannot start (code 10)" etc, etc, etc. So far i have tried everything... including:
Downloading Realtek driver "bundle" if you will... "WMDxxx.exe" or whatever.... only to recieve the "rtkvac.sys not found" error
Downloading all possible drivers directly from Realtek.... nothing (including vista and even xp drivers)
Windows update.... nothing... either does not acknowledge and says cannot find driver or.... says that the most recent driver is installed.
Updated My bios version..... older computer and a newer bios was available........... nothing.
Control Panel... device manager... uninstall/reinstall/update driver.... nothing
There is countless, poorly detailed, or obvious solutions in all the threads that i have sorted through. Unfortunately i have tried all of the obvious and not so obvious suggestions i could find and i have failed miserably. Of all the things that have worked for some, none have worked for me... So i hope you have better luck with that