Installation guide

Chapter 5. McBIOS Configuration
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5.5.7.1 Stagger Power On Control
In a PC system with only one or two drives, the power can supply 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
system 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
ability 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 designed to meet short-term startup power demand as
well as steady state conditions.
RAID controller has included the option for customer to select the disk drives
sequentially stagger power up value. The values can be selected from 0.4ms to
6ms per step which powers up one drive.
5.5.7.2 Time to Hdd Low Power Idle
This option delivers lower power consumption by automatically unloading
recording heads during the setting idle time. The values can be selected
“Disabled” or within the range 2 to 7 minutes.
5.5.7.3 Time to Hdd Low RPM Mode
This function can automatically spin disks at lower RPM if there have not been
used during the setting idle time. The values can be selected “Disabled” or
within the range 10 to 60 minutes.
5.5.7.4 Time to Spin Down Idle HDD
This function can automatically spin down the drive if it hasn’t been accessed for
a certain amount of time. This value is used by the drive to determine how long
to wait (with no disk activity, before turning off the spindle motor to save power).
The values can be selected “Disabled” or within the range 1 to 60 minutes.
5.5.7.5 SATA Power Up In Standby
SATA Power Up In Standby (power management 2 mode, PM2) is a SATA disk
drive configuration which prevents the drive from automatic spin-up when power
is applied. “Enabled” option allows the drive to be powered-up into the Standby
power management state to minimize inrush current at power-up and to allow.
The controller to sequence the spin-up of devices. It is mainly for
server/workstation environments operating in multiple-drive configurations.