Enter the Ctrl M bios, and create a new array with these drives.  Initialize the array, making sure you select the new array only,  then go into Drive Management and assign a drive letter to the new array.   Then you should be able to use the newly available space.   Regards, 
Have a 2800 running Win SBS 2003.   Currently set up with PERC 4e/di RAID 5 with three drives.   I'm running out of storage space and want to add three drives - not add them to the curent RAID array, but make an additional array.    I installled the drives, and the right side green lights came on.   They don't show up in system manager, computer management, etc.    How do I get these drives to be recognized?
Adding drives to PERC 43/di Dell 2800 - Help