Multiple RAID arrays on HP Smart Array E200i controller
Solution 1:
Yes; this should be possible via the ACU (Array Configuration Utility) from your OS - This means no downtime if your HDs and Cage are HotPlug (Look for reddish/pink parts in HP Servers - They are allways HotPlugable) or via the OptionROM at boottime. The Restrictions regarding RAID Levels apply the same as with your original Disks. Raid 0+1 only without optional Cachememory (which you seem to have installed).