Asus Crosshair II Formula - Manual (Page 156)

5-34 Chapter 5: Software support
5.4 RAID configurations
The motherboard comes with the NVIDIA ® nForce ® 780a SLI™ Southbridge RAID
controller that allows you to configure ID� and Serial ATA hard disk drives as RAID
sets.
5.4.1 RAID definitions
RAID 0 (Data striping) optimizes two identical hard disk drives to read and write data
in parallel, interleaved stacks. Two hard disks perform the same work as a single
drive but at a sustained data transfer rate, double that of a single disk alone, thus
improving data access and storage. Use of two new identical hard disk drives is
required for this setup.
RAID 1
(Data mirroring) copies and maintains an identical image of data from one
drive to a second drive. If one drive fails, the disk array management software directs
all applications to the surviving drive as it contains a complete copy of the data in
the other drive. This RAID configuration provides data protection and increases fault
tolerance to the entire system. Use two new drives or use an existing drive and a
new drive for this setup. The new drive must be of the same size or larger than the
existing drive.
RAID 0+1 is data striping and data mirroring combined without parity (redundancy
data) having to be calculated and written. With the RAID 0+1 configuration you get
all the benefits of both RAID 0 and RAID 1 configurations. Use four new hard disk
drives or use an existing drive and three new drives for this setup.
RAID 5 stripes both data and parity information across three or more hard disk drives.
Among the advantages of RAID 5 configuration include better HDD performance,
fault tolerance, and higher storage capacity. The RAID 5 configuration is best suited
for transaction processing, relational database applications, enterprise resource
planning, and other business systems. Use a minimum of three identical hard disk
drives for this setup.
JBOD
(Spanning) stands for Just a Bunch of Disks and refers to hard disk drives
that are not yet configured as a RAID set. This configuration stores the same data
redundantly on multiple disks that appear as a single disk on the operating system.
Spanning does not deliver any advantage over using separate disks independently
and does not provide fault tolerance or other RAID performance benefits.
If you want to boot the system from a hard disk drive included in a created RAID
set, copy first the RAID driver from the support DVD to a floppy disk/USB device
before you install an operating system to the selected hard disk drive. Refer to
section 5.5 Creating a RAID driver disk for details.