XPS 630i and Adaptec RAID 2405 not recognized...

So, after reading that the BIOS in XPS 630i doesn't support RAID 5, I picked up a new Adaptec 2405 RAID controller, and dropped it in my 630i.  Not recognized.  I noted that one page on Adaptec's site said Win8 was supported, and another page said it wasn't, so I wiped the machine and dropped Win7 Pro/64 on it.  According to one of those above pages, Win7 *is* supported with the native Windows drivers.  Also noted that NOTHING in the manuals for the 630i say that non-Dell RAID *isn't* supported, so I was hoping to get the Adaptec solution up and running.

New Win7/64 installation, still not recognized.  Disabled nVidia RAID driver, still no-go.  No setting in BIOS to completely disable nVidia's build in RAID, except for enabling/disabling on a drive-by-drive level.  Tried toggling this for all SATA drives in BIOS; no effect.  Uninstalled adapter, plugged back in.  Never got a Windows "new hardware detected" popup; still not recognized.  Can't install Adapted specific drivers because I can't get Windows to recognize the device.

Is there a trick, or did Dell conveniently hamstring being able to use RAID in these machines other than their own severely limited RAID0/RAID1 configurations?  Do I need to try Linux (or am I still because the 630i is hamstrung)?

Thanks, all suggestions welcome!

SteveInReno

Edit: can't go further with Adapted until I find out whether Adapted RAID (and specifically the 2405) is supported in the 630i box.