82801BA Datasheet, PDF (133/498 Pages) Intel Corporation – Intel 82801BA I/O Controller Hub 2 (ICH2) and Intel 82801BAM I/O Controller Hub 2 Mobile

Functional Description
5.12
Power Management (D31:F0)
Features
• ACPI Power and Thermal Management Support
— ACPI 24-Bit Timer
— Software initiated throttling of processor performance for Thermal and Power Reduction
— Hardware Override to throttle processor performance if system too hot
— SCI and SMI# Generation
• PCI PME# Signal for Wake Up from Low-Power states
• System Clock Control
— ACPI C2 state: Stop-Grant (or Quickstart for the 82801BAM ICH2-M) state (using
STPCLK# signal) halts processor’s instruction stream
— ACPI C3 State (82801BAM ICH2-M): Ability to halt processor clock (but not hub
interface or memory clock)
— 82801BAM ICH2-M: CLKRUN# protocol for PCI clock starting/stopping
• System Sleeping State Control
— ACPI S1 state (82801BA ICH2): Like C2 state (only STPCLK# active, and SLP#
optional)
— ACPI S1 state (82801BAM ICH2-M): Powered On Suspend (POS)
— ACPI S1 state: Like C2 state (only STPCLK# active, and SLP# optional)
— ACPI S3 state - Suspend to RAM (STR)
— ACPI S4 state - Suspend-to-Disk (STD)
— ACPI G2/S5 state - Soft Off (SOFF)
— Power Failure Detection and Recovery
• Streamlined Legacy Power Management Support for APM-Based Systems
• 82801BAM ICH2-M: Intel^® SpeedStep^TM transition logic
82801BA ICH2 and 82801BAM ICH2-M Datasheet
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