This post for the following penguins:
Kernel 2.6.21.x or 2.6.22.x,
sound chip is ATI SB450 HD audio with Realtek ALC851 chipset,
alsamixer shows zero master volume, (and NOT adjustable, thus no sound).
run alsaconf (etch version, not lenny version)
pass parameter to
modprobe snd-hda-intel model=auto
ALSA works with 2.6.20 kernel, without any tweak.
ALSA does not work with 2.6.21/2.
Read following page with changes with 2.6.21.x (ALC861 with Toshiba)
Read ALSA-Configuration.txt in kernel source
However, neither of following works
modprobe snd-hda-intel model=toshiba
It was confusing.