open /etc/lilo.conf or /etc/grub.conf with an editor while logged in as root and add this:
append "/dev/hdx=ide-scsi"----->x=drive letter, a=ide cable 1 master, b=cable one slave,c=ide cable 2 master etc
that should load it at boot time
or you could add this to /etc/rc.d/rc.local:
modprobe ide-scsi
you may want to just try it at first using "modprobe ide-scsi" from the commandline and make sure it works before adding it to the start up scripts