I thought this might be helpful to any archers that have a Toshiba a105 series laptop ( I have an A105-S2194). The SB450 is a bitch of a chipset to get working properly.. I have spent the last week scouring google, and other places. This is fairly kludgey but works for me. Your mileage will probably vary
The first issue was that alsamixer was showing the controls for my Modem
This was fixed by adding the following to /etc/modprobe.conf
option snd-hda-intel probe_mask=8 model=auto
The card still won't work after this step. But it does force alsa to use the sound card instead of the modem.
I noticed that every time I loaded or unloaded the module, dmesg would have an error about acpi being disabled. I tried turning acpi off and managed to stall my system for several minutes.
On a whim I looked at lsmod after unloading snd-hda-intel and discovered that most of the sound modules were still present. I removed them from rc.conf leaving only snd-hda-intel. after a reboot I got sound, with pops and clicks. however mpg123 sucessfully played an mp3 file.
the pops and the clicks were remedied by muting the cd volume control.
The only app I had issues with afterward was Pidgin. It didn't play sounds with alsa output. I changed it to manual and used