User`s manual

Chapter 4: AMI BIOS
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PWM Cycle), Balanced (@50% of PWM Cycle), and Energy Saving (@30% of
PWM Cycle).
Fan1 ~ Fan 6 Reading
This feature displays the fan speed readings from fan interfaces Fan1 through
Fan5.
CPU Vcore, AVCC, 3.3Vcc, 12V, V_DIMM, 5V, -12V, 3.3Vsb, and Vbat
ACPIConguration
Use this feature to congure Advanced Conguration and Power Interface (ACPI)
power management settings for your system.
High Performance Event Timer
Select Enabled to activate the High Performance Event Timer (HPET) that produces
periodic interrupts at a much higher frequency than a Real-time Clock (RTC) does in
synchronizing multimedia streams, providing smooth playback and reducing the de-
pendency on other timestamp calculation devices, such as an x86 RDTSC Instruc-
tion embedded in the CPU. The High Performance Event Timer is used to replace
the 8254 Programmable Interval Timer. The options are Enabled and Disabled.
ACPI Aware O/S
Enable ACPI support if it is supported by the OS to control ACPI through the Operat-
ing System. Otherwise, disable this feature. The options are Yes and No.
ACPI APIC Support
Select Enabled to include the ACPI APIC Table Pointer in the RSDT (Root System
Description Table) pointer list. The options are Enabled and Disabled.
APIC ACPI SCI IRQ
When this item is set to Enabled, APIC ACPI SCI IRQ is supported by the system.
The options are Enabled and Disabled.
Headless Mode
This feature is used to enable the system to function without a keyboard, monitor
or mouse attached The options are Enabled and Disabled.
ACPI Version Features
The options are ACPI v1.0, ACPI v2.0 and ACPI v3.0. Please refer to ACPI's website
for further explanation: http://www.acpi.info/