Thanks for the reply,
I had a look on the Adaptec and Promise website, and while there is no info regarding my orginal question, I am leaning *away* from my idea of resurrecting the ol' P133.
It seems that these RAID cards do have linux drivers, but you may be linked to a particular distro and version. One Promise card had drivers for Caldera, Suse, and Redhat; but the most recent RH drivers were for 7.3
I have no idea whether those drivers would work on newer releases like RH8 or even different distros (I'm on MDK9 currently), but while Promise has Windows drivers out the wazoo, their Linux support seems much more sparse...
I was hoping to use the old Pentium to save some $$ but I may just be better off getting a cheap Duron or Celeron and running a software RAID 1.
Also, if I'm still too dumb to get the RAID working properly, I can still cron regular backups to the second HD