I built a new badass workstation for home and I was attempting to capitalize on using SAS drives for increased speed for my system drives, but still use my 5 x 500gb sata drives for storage.   So I purchased the the ASUS P6T Deluxe motherboard which has two onboard SAS ports and 6 onboard SATA ports.   The SAS ports have a built in RAID controller that can do RAID-0 and RAID-1.   The SATA ports can do RAID-0, RAID-1, RAID-5, RAID-10, etc.    In order to get them to both do RAID you have to do the following.   If you enable the SATA drives for RAID, the SAS drives become missing/undetected.

-Enable SAS

-Setup SATA drives for RAID.

-Control+i to get into raid management for SATA drives, and configure how you want them.

-Go back into BIOS and set SATA up as IDE

-Boot and control+m to get into SAS drive management and make sure its activated.

-Reboot and install OS on sas drive.

-After OS is installed, reboot, and change SATA drives from IDE to ACHI and reboot again.

-After Windows loads, install the Intel Matrix Storage Manager and drivers and it will detect your SATA RAID drives…