[CentOS] Dell R605 w/ Perc 6/i problem

I think there was just a thread 'bout this, and I didn't pay attention...
and then I walked into our smallest server room to rebuild a server with
CentOS... and that's what it is. The problem I'm having is this: there are
two 1T SAS drives, raided, via the controller. There's also a 750G SATA
drive. The Dell test suite sees it, and reports that SMART says it's fine.
However, no matter what I do, the BIOS doesn't see it, and when I boot to
linux text, fdisk only sees the raided 1t.

Clues for the poor? I want to put the system on the SATA drive, leaving
the raid for data.

       mark