Moving From Native IDE to RAID OnChip SATA Type Causes Windows Boot Failure

Hello, thanks for taking a look at the problem I'm encountering.

I installed Windows 7 a few months ago and the install went rather well.  I installed Windows 7 on a dedicated SATA HDD (C Drive) and I have another SATA drive that I keep my audio and video files on (D Drive).  Well. . .today I decided to make a change.

I bought two new HDD's that I'd like to run in RAID-1 that will replace my current D: Drive.  So, I crack open the manual for my motherboard (Gigabyte GA-MA78GM-S2H) and it says I need to change the following in the BIOS:

Under the "Integrated Peripherals" menu set "OnChip SATA Controller" to "Enabled" (it was already enabled), secondly set "OnChip SATA Type" to "RAID" (it was "Native IDE"), lastly set "OnChip SATA Port4/5 Type" to "As SATA Type" (it was unset).

So, I've noticed that after I change "OnChip SATA Type" to from "Native IDE" to "RAID" and reboot my PC that Windows doesn't load :-/  Instead, it loads the "Windows Startup Recovery Manger" which runs for a while and then indicates that it cannot repair the problem.  Going back into the BIOS and changing the  "OnChip SATA Type" back to "Native IDE" allows me to successfully boot Windows 7 again.

So, what gives?  I really don't understand what "Native IDE" means, or for that matter what "OnChip SATA Port4/5 Type" means in the BIOS, but I need to change these settings so that I can build my new RAID-1.  Can you tell me what's going on and how I might progress. . .

I think that maybe I need to install the SATA controller driver from the motherboard manufacturer so that Windows 7 can recognize the hard drive. . .but that's just a guess.  If that's the case I guess the question becomes, how do I install the SATA controller drivers AFTER Windows 7 has already been installed.

Thank you