Can I have both IDE and SCSI Drives?
Mixing SCSI and IDE drives can be a problem if you want the root disk to be scsi. The short answer is that you can if your BIOS lets you select which drive to boot (if not, you would have to boot from a floppy). Assuming everything else is in place, "defbootstr hd=Sdsk" should work. See SCSI for a full discussion of this.
This was found at
pcunix.com and may help clue you in on the problems. Check out the link for further info or try your own search there.