Unable to install Windows 7 Asus M2A-VM Raid Driver?

I have just had a Gigabyte GA-MA69G-S3H motherboard and in DESPERATE need of Asus M2A-VM Raid Driver to finish building Windows 7. My problem is, when I boot from the Windows 7 DVD and get to the point to where I can load the RAID driver... the setup program installss the "ATI ACHI Compatible RAID Controller" just fine but it detects the volume as "Unallocated Space" even if a partition already exists. Meanwhile, there is a warning at the bottom of the screen that says "Your Systems BIOS does not support booting to this device...". Can any body help me out here?