35
*Serial ATA Combined and Non-Combined mode
Mode
Option 1
Option 2
Option 3
Combined
•
Serial ATA
devices
•
Parallel
ATA
devices
•
Maximum of 2
each
X X
Non-
Combined
X
•
Parallel
ATA
devices only
•
Maximum of 4
•
Serial ATA de-
vices only
•
Maximum of 2
Serial ATA RAID connectors controlled by VT8237/VT6420
VIA VT8237/VT6420 supports stripping (RAID 0) and mirroring (RAID 1),
separately.
With stripping, identical drives can read and write data in parallel to increase
performance. Mirroring increases read performance through load balancing
and elevator sorting while creating a complete backup of your files.
It offers RAID 1 mirroring (for two drives) to protect data. Should a drive that is
part of a mirrored array fail, VIA VT8237/VT6420 uses the mirrored drive
(which contains identical data) to assume all data handling. When a new re-
placement drive is later installed, VIA VT8237/VT6420 rebuilds data to the
new drive from the mirrored drive to restore fault tolerance.
RAID 0 (Stripping) RAID
1
(Mirroring)
Configures multiple drives so that sectors
of data are interleaved within an array.
When a disk member fails, it affects the
entire array. Performance is better than a
single drive since the workload is bal-
anced between array members. This array
mode is designed for high performance
systems. Identical drives are recom-
mended for performance as well as data
storage efficiency. The disk array data
capacity is equal to the number of drive
members times the smallest member
capacity.
Configures an array of 2 drives to write
duplicate data and read in parallel. It per-
forms reads using advanced data
handling techniques that distribute the
workload in a more efficient manner than
using a single drive. When a read request
is made, it selects the drive positioned
closest to the requested data, and then
looks to the idle drive to perform the next
read access.
VIA VT8237/VT6420 stripped arrays can double the sustained data transfer
rate of SATA/150 drives. VIA VT8237/VT6420 fully supports SATA / 150 speci-
fication of up to 150 MB/sec per drive, depending on individual drive
specifications.
