DATOptic ARC-1680 Series - Manual (Page 139)

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WEB BROWSER-BASED CONFIGURATION
Multiples Of 1G: If you have 123 GB drives from different ven-
dors; chances are that the capacity varies slightly. For example,
one drive might be 123.5 GB, and the other 123.4 GB. Multiples
Of 1G truncates the fractional part. This makes capacity for both
of these drives so that one could replace the other.
No Truncation: It does not truncate the capacity.
6.8.2 HDD Power Management
Areca has automated the ability to manage HDD power based
on usage patterns. The “HDD Power Management” allows you to
choose a “Stagger Power On Control”, “Low Power Idle”, “Low
RPM” and completely “Spins Down Idle HDD”. It is designed to
reduce power consumption and heat generation on idle drives.
6.8.2.1 Stagger Power On Control
In a PC system with only one or two drives, the power can sup-
ply enough power to spin up both drives simultaneously. But in
systems with more than two drives, the startup current from
spinning up the drives all at once can overload the power supply,
causing damage to the power supply, disk drives and other sys-
tem components. This damage can be avoided by allowing the
host to stagger the spin-up of the drives. The SAS/SATA drives
have support stagger spin-up capabilities to boost reliability.
Stagger spin-up is a very useful feature for managing multiple
disk drives in a storage subsystem. It gives the host the abil-
ity to spin up the disk drives sequentially or in groups, allowing
the drives to come ready at the optimum time without straining
the system power supply. Staggering drive spin-up in a multiple
drive environment also avoids the extra cost of a power supply