SATA drive no workie

I have a MachSpeed motherboard (actually made by Jetway) that does not have SATA support (VIA 440A chipset circa 2004).

I recently purchased a new SATA drive, RAID adapter (VIA 6421), and cables. Once installed and connected, the drive is visible and active in XP. However, the BIOS will not allow the drive to be recognized as a standalone drive.

If I attempt to install Windows XP on the SATA drive, and press F6 to install 3rd party RAID drivers, all goes well, I can get the installation to begin, and copy files/make folders on the disk.

Once the Windows installation needs to reboot, the drive is treated as if were never there (not recognized in BIOS at reboot) and the machine boots back into the CD Rom and we start the vicious cycle.

I understand that the BIOS needs to have SATA support but don't understand WHY that is so if the drive can be recognized by XP ! ? !

So the question is;
Does anyone have a solution for this other than updating the BIOS (neither Jetway or Machspeed has a BIOS update newer than 2004)?

If not, does anyone know of a BIOS update newer than 2004 that will address this?

Thanks to all in advance.