Dynamic Power Saver Mode; Power Regulator; Power Capping For Each Server Blade - HP BladeSystem c3000 Technology Brief

Connecting with no power redundancy configured
If no power redundancy is configured, the total power available is defined as the power available
from all power supplies installed (six power supplies installed = up to 7200W). Any power supply or
AC line failure may cause the system to power off.
The Onboard Administrator manages power allocation rules of various components and can limit
overall power capacity for the enclosure. More information on power management is available in the
technology brief entitled "Managing the HP BladeSystem c-Class," which is available at this URL:
www.hp.com/servers/technology

Dynamic Power Saver mode

Dynamic Power Saver mode provides power load shifting for maximum efficiency and reliability.
Dynamic Power Saver technology, first introduced with the BladeSystem p-Class1U power enclosure,
maximizes power supply efficiency to provide real customer power savings that result in capital
savings. Power supply efficiency is simply a measure of AC watts input in versus DC watts out: At 50
percent efficiency, 2000W in would equal 1000W out. The difference is wasted energy, which
generates unnecessary heat.
Dynamic Power Saver mode is active by default since it saves power in the majority of situations.
When enabled, Dynamic Power Saver mode saves power by running the required power supplies at
a higher rate of utilization and putting unneeded power supplies in a standby mode. Dynamic Power
Saver uses the fact that most power supplies will operate less efficiently when lightly loaded and more
efficiently when heavily loaded. A typical power supply running at 20 percent load could have an
efficiency rating as low as 60 percent. However, at 50 percent load it could be up to 90 percent
efficient, providing a significant savings in power consumption.
Dynamic Power Saver is enabled by the Onboard Administrator module. When this feature is
enabled, the total enclosure power consumption is monitored in real-time and automatically adjusted
with changes in demand.
NOTE
In redundant environments, a minimum of two power supplies
are always active, and the maximum load that can be reached
on any power supply is 50 percent. Once the 50 percent load
is reached, another two power supplies are activated to ensure
that redundancy is maintained at all times.

Power Regulator

HP's ProLiant Power Regulator provides iLO-controlled speed stepping for Intel x86 processors. The
Power Regulator feature improves server energy efficiency by giving processors full power for
applications when they need it and reducing power when they do not. This power management
feature enables ProLiant servers with policy-based power management to control processor power
states. Power Regulator can be configured for continuous, static low power mode or for Dynamic
Power Savings mode in which power is automatically adjusted to match processor demand.
Additional information on the HP Power Regulator is provided in the paper titled "Power Regulator for
ProLiant servers," available at

Power Capping for each server blade

Using updated iLO 2 firmware (version 1.30) and updated System ROM/BIOS (dated May 1, 2007),
HP BladeSystem c-Class server blades now have the ability to limit the amount of power consumed.
Customers can set a limit in watts or BTUs per hour. The purpose of this limit is to constrain the amount
of power consumed, which reduces the heat output into the data center. The iLO 2 firmware monitors
.
www.hp.com/servers/power-regulator
.
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