Table of Contents
Advertisement
Four levels of system power management, including:
A true Suspend/Resume mode that can be accessed from
both DOS and Windows applications. (Described in
Chapter 5, Utilizing Power Management.)
The status of various system devices during Auto Suspend,
CPU Standby, Global Standby, and Suspend modes is listed
in the section "Device Status" (later in this appendix).
Hardware
Specific hardware power management includes the
following.
Clock stretching. APM reduces the CPU speed without
adding a wait states when a 0.5-cycle wait state is
needed in case of DRAM access.
Quiet bus. APM inhibits all signals in the AT Bus
except the AT bus cycle. This function saves energy
by reducing the number of unnecessary charges
and discharges.
Modular clocking. APM slows the CPU clock speed
when the CPU is not used. When enabled, modular
clocking reduces CPU power consumption to as low
as 3.2 MHz.
Power-saving devices. APM puts devices that have
power-saving features into Standby mode when they
are not active.
B-2 Other Utilities
APM Idle
CPU Standby
Global Standby
Auto Suspend.
Advertisement
Table of Contents
