SATA ports are all backward and forward compatible.. Thus you can use a SATA II drive on a SATA III port and likewise.. However, if you are planning on buying SATA III hard drives then keep in mind that they cost extra for no apparent benefits.. If you need speed then get SSD.. A single SSD will perform better compared to couple of SATA drives in RAID 0.. But of course they are costly and carry lower capacity..