Ampro Corporation LITTLE BOARD P5X - Manual (Page 92)

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! PM Control by APM — when enabled, it allows operating systems with power management
support to control the modes required for safe operation of shutdown occurrences.
! Video Off Option — sets the conditions under which the BIOS powers down the video
(assuming your video interface supports power management). Select the DPMS option only if
your monitor supports the VESA Display Power Management Signaling standard. H/H
SyNC+Blank turns off the horizontal and vertical sync signals and blanks the video buffer.
Blank Screen only blanks the video buffer.
! Thermal Duty Cycle — CPU temperature may be controlled by an optional fan. When enabled
the CPU performance will be limited by the stop clock interface at the percentage indicated
when the CPU Fan is running.
The power management timers are only configurable if the Power Management option is set to
User Defined. Each timer sets the amount of idle time before the system enters the specified
power-saving mode. These modes are:
! Doze Mode — when enabled and after a set time of system inactivity, the CPU clock speed is
reduced. Other devices remain active.
! Standby Mode — when enabled and after a set time of system inactivity, the CPU clock speed
is reduced, and the disk drives and video monitor are shut down. Other devices remain active.
! Suspend Mode — when enabled and after a set time of system inactivity, all activities except
DRAM refresh are shut down.
! HDD Power Down — when enabled and after a set time of system inactivity, the hard disk
drives are shut down. All other devices remain active.
! Throttle Duty Cycle — selects a percentage of time the CPU runs in Doze Mode.
! ZZ Active In Suspend — controls L2 Cache Sleep signal during Suspend Mode. When
enabled, the ZZ signal will be asserted under certain conditions when entering clock control
mode. NOTE: The L2 cache can not be snooped with the ZZ signal asserted. It must be disabled
in Level 2 power states such as Stop Grant.
! VGA Active Monitor — when enabled, any video activity restarts the Standby Mode timer.
! Soft-Off by PWR-BUTTN — Enables PWR-BUTTN input. A 4 second signal from this input
will cause a power-down of all on-board systems.
! Resume by Ring — Ring Detect on Serial Port 1 will cause an exit from any active power
management mode.
! Resume by Alarm — RTC Alarm will cause power management mode exit.
! IRQ 8 Break Suspend — RTC Interrupt will cause power management mode exit.
! Reload Global Timer Events — any of the Reload Global Timer Events will cause the
Standby Mode timer to be restarted when the event is detected.