The HP Surestore Virtual Array 7100 is a disk storage system that holds a minimum of four and a maximum of 15 disk drives. The array features scalable capacities from 72 GB to 144 GB, with all 18 GB disk drives, and from 270 GB to 540 GB, with all 36 GB disk drives. Disk drive capacities can be mixed within the HP Surestore Virtual Array 7100.Using HP's AutoRAID technology, the array controller automatically selects RAID 0/1 or RAID 5DP (RAID 5 Double Parity). The array can be ordered with a single controller for non-redundant data storage, or with dual controllers for redundancy. Each controller has two DIMM slots to hold NVRAM for cache and maps.