I'm trying to RAID two SSD's in raid 0 to install games on, but I want to have my OS running off of my HDD (which it is currently installed on). I have the HDD plugged into SATA 5, and the SSD's plugged into SATA 2 and 3 (cable length).
When I set SATA 1-4 to raid, the only options I have for 5-6 is RAID or IDE. When I set SATA 1-4 to AHCI, I cannot set 5-6 to RAID. A simple, but annoying catch 22

How do I set SATA 5-6 to AHCI while maintaining RAID on 1-4?