You didn't say so, sooo ... did you look in Disk Management - you may need to initialize the "disk" first.
DELL 250gb RAID 1 in (0/1) ... and created a 2TB non-dell RAID1 in (2/3) .... bios and OpenManage both see the second RAID volume but nothing shows up in Windows.  have tried everything!   Updated firmware and drivers... firmware:  07.03.05.00 driver:  2.00.35.10 Storport Driver (???): 6.1.7601.17577 Virtual Disks shows the original 250GB volume as "Virtual Disk 1" but  "Windows Disk 0" Virtual Disks show the new 2tb volume as"Virtual Disk 0" but  "Windows Disk 1"  
H200 ... SBS2011 wont see second RAID volume