support for alsa and you soundcard are in the kernel. If you compile the kernel with those devices loaded you can use alsa-util to run alsamixer and unmute your sound (its usually muted by default for some reason, so even if everything works, you have to unmute it.)
Too bad mandrake doesn't use a normal kernel. If you are going to use mandrake, then my suggestion is probably not possible for you.
just in case you wish to do that, and you probably don't -otherwise you wouldn't be using mandrake, here's a link for recompiling a mandrake kernel.