I purchased an early 2008 MacPro some time ago with the Apple RAID card and a single 15K 300 GB SAS drive. Later, I purchased two additional 300GB SAS drives with the intention to upgrade the system disk to a 600 GB RAID 5 array consisting of the three drives. My problem is that I can not add the system drive to the array, so I figured that I have to clone it and boot from the clone first. In the 4th bay I have a 300GB SATA drive which I'm attempting to use as the new one and have tried cloning it with ditto and rsync as outlined in http://www.bombich.com/mactips/image.html However, I am unable to change the boot partition in the system preferences after making the clone. What are my options? Some sources suggest that using a RAID array as the system partition is not a good idea. Why would this be? Has anyone else even tried this?