First off, is this a Promise card or are you using the onboard raid?
I'll assume you mean a specialty Raid card: find the drivers for your promise card--start
here or
here.
You'll need to put the ko files (recommend you compile yourself) into /lib/modules/{kernel name}/kernel/drivers/scsi/. Run (/sbin/)modprobe with the name of the driver. This should enable your sata controller. Next you need to grab the latest version of dmraid for your kernel (available
here ).
Run dmraid -ay. Check under /dev/mapper -- you should see something like driver_ghbbjeifsd and driver_ghbbjeifsd1 where driver is the name of that ko file you grabbed. mount driver_ghbbjeifsd
1 to wherever you want. Voila