NCR 7452, User Manual

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1-12 Chapter 1: Product Overview
Power Management
Power management on the 7452 uses the Advanced Power
Management (APM) BIOS Interface Specification Revision 1.1 as
defined by Intel and Microsoft. The processor board is equipped with
an APM BIOS.
APM defines five system power states:
On
Power on (Maximum Power)
APM Enabled
APM enabled slows the CPU clock and turns off devices
when possible to minimize power consumption while the
system is operating.
Standby
APM standby is a lower power state where the CPU clock
is likely to be stopped. No delay exists when recovering
from this state.
Suspend
Suspend is the system’s lowest power state. A delay exists
when recovering from this state. (Suspend mode is not
present in 586 boards.)
Off
Power off (Minimum Power)
The APM BIOS provides some degree of power management
functionality without any support from the operating system or
application software.
An APM driver is better suited to make power management decisions
for unique peripherals than the BIOS, and can override most BIOS
requests to go into standby, suspend, etc. APM device drivers
provided by NCR with the 7452 are outlined in the Retail TAPS
Programming Help File.
Workstation power on/power off is controlled through a logic level
power switch on the processor board. It can be disabled through
software.