XFX 750a disables PCI SATA card when onboard SATA is set to RAID

[monza]

I have used the instructions in the following article to change the SATA mode to RAID mode on my XFX 750a SLI motherboard:
FAQ: Switching Storage Controllers w/o Reinstalling Windows

However, the motherboard disables booting to the PCI SATA card when the BIOS setting for SATA is RAID. The process works fine when changing the mode to AHCI.

Anyone have any suggestions of getting the RAID drivers into Windows 7 Pro x64 without having to reinstall Windows from scratch? I am stuck at "21. Allow the existing installation of Windows to start up." of the "Example" instructions from the above link.

 

[monza]

I did a lot more searching and found this article in the Microsoft Support:
Error message when you start a Windows 7 or Windows Vista-based computer after you change the SATA mode of the boot drive: "STOP 0x0000007B INACCESSABLE_BOOT_DEVICE"

I tried the specified instructions, but they did not work. However, it did get me thinking. I searched through the "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services" section of Windows Registry for the keyword "RAID," which the search found 3:
nvraid
nvstor
vmsraid

After clicking each subkey, I followed steps 5-6 of the article above and then exited:
5. In the right pane, right-click Start in the Name column, and then click Modify.
6. In the Value data box, type 0, and then click OK.

Upon reboot, I set the onboard SATA controller to RAID and booted the OS. Low and behold, Windows booted! After Windows installed the RAID drivers, I rebooted, again. Everything works great! Keep in mind, I installed the full nVidia driver package for the mobo before making any BIOS changes.

I hope this helps someone with the same issues!