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IDE3/IDE4: Third/Fourth IDE connector
These connectors are for Promise PDC20265R controller only. Connect one
cable to each of the IDE connectors of the mainboard (IDE3 & IDE4 connec-
tor). Please note the color orientation of the cable before attaching it to the
mainboard. If you wish to use the IDE array controller, please refer to the op-
tional “Promise Raid” user’s manual.
Promise PDC20265R
supports striping (RAID 0) or mirroring (RAID 1),
separately.
With striping, identical drives can read and write data in parallel to in-
crease 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, Promise PDC20265R
uses the mirrored
drive (which contains identical data) to assume all data handling. When a
new replacement drive is later installed, Promise PDC20265R
rebuilds
data to the new drive from the mirrored drive to restore fault tolerance.
RAID 0 (Striping)
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 recommended for per-
formance as well as data storage efficiency. The disk array data
capacity is equal to the number of drive members times the smallest
member capacity.
RAID 1 (Mirroring)
Configures an array of 2 drives to write duplicate data and read in
parallel. It performs 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 posi-
tioned closest to the requested data, and then looks to the idle drive
to perform the next read access.
Promise PDC20265R
striped arrays can double the sustained data trans-
fer rate of Ultra ATA/100 drives. Promise PDC20265R
fully supports Ultra
ATA/100 specification of up to 100 MB/sec per drive, depending on indi-
vidual drive specifications.
Note:
Please use an 80-wire, 40-pin cable when connecting an Ultra ATA/100
hard drive to the motherboard IDE3 & IDE4 controller.
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