2 bays but the motherboard and BIOS are common so it should work too (AR5000-MI2). You can take a backup of the BIOS chip with a CH341 programmer to be safe, but the chip is located behind the cooler - so you have to basically remove all the screws (and repaste the CPU).mine definitely requires both PCI devices to be passed through, is yours the 4 bay or 2 bay?