Help Setting Up SSD and HDD on P9X79 WS

I have a Px79WS and have a samsung 256GB SSD and 2 WD Black 2TB HDD

I want to set it up with the SSD as the main drive and the 2 HDD in raid 1. So here is what I did.

Only connected the SSD to the Intel Sata 6GB/s and installed the OS (win 7 64). I remember reading that this is how it should be done.

Everything went fine, installed all the driver updates etc.

Then I connected the 2 HDD to the Marvel 6GB/s connectors, went into BIOS and changed to RAID from AHCI.

Also did CTL M and set up the RAID array with the 2 drives.

Changed boot order to the Samsung SSD then to Marvel, but when it boots i get BSOD.

Am i doing something wrong? Do I need to update the BIOS version? Not sure what I am doing wrong? Should I have had everything hooked up before installing the OS? Or should I have them hooked up to different controllers?

Thanks