HP A3550A - High Availability Disk Arrays Model 20 Storage Enclosure User Manual page 69

Physical disk
configuration
RAID-5 group with 5
disk modules
RAID-1 mirrored pair
RAID-1/0 group with 6
modules
RAID-1/0 group with 10
modules
1-32
Read performance Write performance
Up to 5.0 with Up to 1.25 with
5-module group 5-module group
1.0 1.0
Up to 3.0 with Up to 3.0 with
6-module group 6-module group
Up to 5.0 with Up to 5.0 with
10-module group 10-module group
Tolerance for single
disk module failure?
Yes
Yes
Yes
Yes