I have the same problem that the user in "Dummy Output in Ubuntu 14.04".
The difference is that cat /proc/asound/card0/codec* | grep Codec outputs:
cat: /proc/asound/card0/codec*: No existe el archivo o el directorio
(It's in Spanish, it means it cannot find the file or directory)
More info:
$ sudo modprobe snd-hda-intel
modprobe: FATAL: Module snd-hda-intel not found.
$ sudo alsa force-reload
Unloading ALSA sound driver modules: (none loaded).
Loading ALSA sound driver modules: (none to reload).
$ sudo aplay -l
aplay: device_list:268: no soundcards found...
$ lspci | grep -i audio
00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset Family
High Definition Audio Controller (rev 04)
$ lspci -v | grep audio
(nothing)
$ locate snd-hda-intel
(nothing)
$ lsmod | grep snd
(nothing)
sudo lspci -nnk | grep -A5 Audio
– Braiam Sep 14 '14 at 13:20