I have Debian GNU/Linux amd64 unstable/sid and before I finished setting everything up, alsa used my integrated audio-chip (part of nForce 4 Ultra) with snd_intel8x0 as a primary device just fine.
What does the following command print out for you?
You should get something like
1 [CK804 ]: NFORCE - NVidia CK804
NVidia CK804 with ALC850 at 0xc5103000, irq 66