Alienware 17-R3, RAID/AHCI

Hi,

I noticed in the bios that the original setting for the two HDD's that I have is set on RAID.

PM951 NVME & Seagate HDD

I'm a little bit confused, cause I thought this laptop does not have RAID capability, and if it does have it, why are the two hard disks so mismatched and configured in RAID? If someone has any information on this, please share, thank you!