Firstly, please be aware that changing the motherboard configuration from AHCI to RAID will require an OS reinstallation. In other words, if your operating system has already been installed in AHCI, you will need to format the disk and reloaded after you change the BIOS to RAID mode.
If your system is freezing on the Ctrl+I prompt screen, then my first troubleshooting recommendation would be to test booting the system with only one hard drive installed. If that works, connect a second one and so on, until you find the device that triggers the issue.
Tried. Started out with 2x 500g WD Black, took it down to 1, a couple Blue, some SSD/600's then none. The frustrating component here is that I have a 2nd board (replacement), built in a system with different components, and it's doing the same thing.
edit: board is on the current bios ver.