The motherboard uses the Intel 82801GR I/O Controller Hub (ICH7-R) for RAID support.
This has four SATA ports and one IDE channel.
You can install the operating system on a single SATA drive with the BIOS SATA configuration set to RAID. Then, you can connect your old RAID array and it will be detected as the previous RAID setup was. Single drives are allowed to be connected to one of the 4 SATA ports in RAID mode.
You may need to install the ICH7-R RAID driver using the F6 installation method on some operating systems. The boot order will need to be set in the BIOS.