Setting the SATA ports to RAID mode in the BIOS/UEFI would automatically run drives in AHCI mode (so you get NCQ, TRIM, etc) if they're not part of a RAID array. You would've been better off sticking to RAID.
As for the driver you linked to, it's for both AHCI and RAID.
Intel® RSTe AHCI & SCU Software RAID driver for Windows
It appears to be specific to Intel server motherboards, though.