82830MP Datasheet, PDF (125/159 Pages) Intel Corporation – Intel 830MP Chipset: 82830MP Graphics and Memory Controller Hub (GMCH-M)

Intel^® 830MP Chipset
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5.5.3 Intel 830MP Chipset System and CPU States
Table 34 shows the state combinations that 830MP supports.
Table 34. Intel 830MP Chipset System and CPU States
Global (G) State Sleep (S) State
CPU (C) State
Processor State
G0
S0
C0
Full On
G0
S0
C1
Auto-Halt
G0
S0
C2
Quick Start (M)
Stop Grant (DT)
G0
S0
C3
Deep Sleep
G1
S1
C3
Deep Sleep
G1
S3
Power off
Power off
G1
S4
Power off
Power off
G2
S5
Power off
Power off
G3
NA
Power off
Power off
Description
Full On
Auto Halt
Quick Start
Stop grant
Deep Sleep
Power On Suspend
Suspend to RAM
Suspend to Disk
Hard Off.
Mechanical Off.
5.5.4
5.5.4.1
5.5.4.2
5.5.4.3
Intel 830MP Chipset CPU “C” States
Full-On (C0)
This is the only state that runs software. All clocks are running, STPCLK# is deasserted and the
processor core is active. The processor can service snoops and maintain cache coherency in this state.
Auto-Halt (C1)
The first level of power reduction occurs when the processor executes an Auto-Halt instruction. This
stops the execution of the instruction stream and greatly reduces the processors power consumption. The
processor can service snoops and maintain cache coherency in this state.
Quickstart (C2)
The next level of power reduction occurs when the processor is placed into the Quick start state by the
assertion of STPCLK#. Mobile Quickstart state is a lower power version of the desktop Stop Grant state.
The processor can service snoops and maintain cache coherency in this state.
The system can transition from the C0 state to the C2 state for several reasons.
Software. C2 is entered when software reads the Level 2 Register. This is an ACPI defined register but
BIOS or APM (via BIOS) can use this facility when entering a low power state.
Throttling. This function can be enabled or disabled via a configuration bit. When this function is
enabled STPCLK# will be asserted to place the processor into the C2 state with a programmable
duty cycle. This is an ACPI defined function but BIOS or APM (via BIOS) can use this facility.
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Datasheet
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