Compaq External RAID Controller & Subsystem Infortrend Operation Manual page 152

should work fine with most drives. Changing this setting is not
recommended unless some particular bus signal issues occur.
All SATA/ATA-based system connects only one drive per
SATA/ATA channel. This helps to avoid single drive failure from
affecting other drives. The maximum mechanical performance of
today's drives can reach around 30MB/sec (sustained read). This is
still far below the bandwidth of a drive channel bus. Setting the
SATA/ATA bus speed to a lower value can get around some
problems, but will not become a bottleneck to system performance.
Mind that the SATA/ATA speed is the maximum transfer rate of
SATA/ATA bus in that mode. It does not mean the drive can
actually carry out that amount of sustained read/write performance.
For the performance of each drive model, please refer to the
documentation provided by drive manufacturer.
Infortrend
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