When exiting bios hit F10 to enter the NVRaid utility. If it shows the array as striped, its splitting the data.
I'm not sure of the effect of a defrag on a raid array? If yours is a fairly recent build you shouldn't have a need to defrag. You pose an intresting question, I'll have to do some research.
*edit*
It looks like the general consensus is that Raid arrays can and should be defraged just as a single drive
"At Microsoft, the Share Point server is a SAN configuration with a 475GB partition with 650GB of compressed data and 20GB changing daily. Microsoft uses Raxco Software?s PerfectDisk®to defragment this environment. The benefit of disk defragmentation comes not from locating physical clusters on the disk but from reducing file system overhead before any physical disk I/O occurs. Once this concept is understood, the need for defragmentation in large RAID or SAN environments becomes obvious. ©2003 Raxco Software, Inc. All rights reserved.PerfectDisk is a registered trademark of Raxco Software, Inc. All other names are trademarks or registered trademarks of their respective owners".
