Reinstalled Windows and no longer have Stereo Mix

I had to reformat my computer because it was in bad shape, Windows I have now is Vista home premium 32 bit.

I used to use Stereo Mix for recording my computer sounds. I had a use for this again but was unable to find Stereo Mix in my computers recording devices, I tried to right click and show disabled devices but it is still not there, Also I tried to go in to control panel and update the audio driver, but it said they are upgraded already? Not sure if theres another way to update them by downloading a driver or something.

question is, how can I get stereo mix back? I know my computer supports it because I have used it so much before.

Thanks in advance.

thanks, I googled what my device is called on control panel got to realtek website and downloaded a codec updates from there, restarted pc and have Stereo mix again.