ohoh - this a part of the Linux downside.untarred the file that I downloaded from Realtek, and read the "readme" file. Then I doubleclicked on "install".
If it was a tarball it was not a .deb file and not directly possible to install in a debian based distro as Mint. You could install it with alien, look here:
http://www.linuxmint.com/wiki/index.php ... eb_package
The post with /etc/modules had to do with an old ISA card. There is also a kernel issue here - 2.20-16 gives problems with sound too I think....