Hello, I finally got round to installing and setting up my RAID5 array using a Rocket Raid 2220 card. Had 2x300 GB drives, new and empty + 1x 300 GB drive already full of archived data. Out of this, the aim is to set up a RAID 5 using all three drives, 900GB raw for 600 GB of redundant storage. My 300GB of archived data is to fill half of this redundant storage. Hmm, how to set up the RAID 5 given that the card needs to reformat all three drives to make it work.. ? That's where my problems started. Read on to see where i failed miserably. Here's what I did: 1. Connected the new 2x300 GB drives to the card, initalised them, and set up a small JBOD of 300GB. 2. The new JBOD appeared in Finder (OS 10.3.9) as an unformatted 300GB drive. Used Disk Utitlity to format it in HFS+ 3. Connected the (full) legacy 300GB drive to the computer, and transferred the 300GB over to the JBOD, 4. Moved the legacy 300GB drive to the RAID card, and initialised (erased) it. 5. Used the card's ' Online Migrate / Change RAID level' to change the 300GB JBOD into a new RAID5 array using all three drives, with 600GB of redundant storage (half this space will be taken by the migrated data (300GB) from the JBOD) 6. After 13 hours, the process is finally finished. Hurry! My precious 300GB of archives is still there! Gadzooks! I can't access the extra 300 GB of redundant storage Finder shows a mounted partion of 300GB, full of my data, which I assume is now sitting on a RAID 5 array, but where is the other 300GB of space? Rebooting and restarting Disk Utility shows a (virtual) drive of 600 GB (actually 558.6GB but lets not quibble), with a single partition of 300 GB. It seems OSX can't access the empty space or add an extra partion without erasing the entire virtual drive even tho the space is empty Now I'm on the short bus up the brown creek without a paddle What did I do wrong? How can I access my full 600 GB of RAID and still keep my 300 GB of archives? Any ideas would be appreciated (Especially from CanadaRAM ) .. RedTomato ..