I have an old SoundBlaster ISA card. The configuration during install told me to run sndconfig after install, which I did. It found no PCI or PnP devices, and asked if I had an ISA card. I replied YES, and it displayed correct choices for I/O port, interrupt, etc. It then failed with a modprobe error on sound-slot-0 trying to load sb.o.gz
The /etc/modules.conf had nothing at all in it for sound. I added alias sound sb to /etc/modules.conf and tried again, and it worked. After it finished, it had removed my "alias" line and added several of its own.