Intel 440GX manual Power Button Implementation

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Design Checklist

•The system reset button has typically been connected indirectly to the PWROK input of the PIIX4/PIIX4E. This technique will not reset the suspend well logic, which includes the SMBus Host and Slave controllers. To reset the hardware in the suspend well, the reset button should be connected to the RSMRST# input of the PIIX4/PIIX4E. Assertion of RSMRST#, via a reset button, will result in a complete system reset. RSMRST# assertion will cause SUS[A-C]# to assert which results in the deassertion of PWROK if SUS[A:C]# controls the power supply PS-ON control signal. The deassertion of PWROK will cause the PIIX4/PIIX4E to assert PCIRST#, RSTDRV, and CPURST.

•In the reference schematics, 3VSB is generated from 5VSB on the power supply connector. The Zener diode, MMBZ5226BL, acts as a voltage regulator which clamps the standby voltage at 3.3V. The 0.1uF and 10uF caps are for noise decoupling and the 56 ohm series resistor is used for current limiting. This Zener diode and 56 ohm resistor should be validated to make sure the standby voltage is clamped to 3.3V. The series resistor may need to be tuned based on the standby current requirements of the board. As the 3VSB is required to supply more current, the voltage will drop slightly. Also note that the Zener being used requires approximately 20mA to sustain 3.3V, however a different Zener diode requiring less current may be used. Refer to the schematics for implementation details.

•RI# can be connected to the modem if this feature is used. To implement ring indicate as a wake event, the source driving the RI# signal must be powered when the PIIX4E suspend well is powered.

•SUSC# is connected to PS-ON (pin 14) of the power supply connector through an inverter to control the remote-off function.

•PCIREQ[3:0]# is connected between the PIIX4E and the PCI bus. Bus master request are considered as power management events.

•Connect SMBCLK and SMBDATA to 2.7K ohm (approximate) pull-up resistors to VCC3, and route to all DIMM sockets, PIIX4E, CKBF, LM79, LM75, and MAX1617. The 2.7K pull-up may not be sufficient for all these loads and their associated trace lengths. This needs to be considered on a design by design basis.

•SMBALERT# is pulled up to 3VSB with an 8.2K ohm (approximate) resistor.

3.15.1Power Button Implementation

The items below should be considered when implementing a power management model for a desktop system. The power states are as follows:

S1 - POS (Power On Suspend - CPU context not lost)

S2 - POSCCL (Power On Suspend CPU Context Lost)

S3 - STR (Suspend To RAM)

S4 - STD (Suspend To Disk)

S5 - Soft-off

•Wake: Pressing the power button wakes the computer from S1-S5.

•Sleep: Pressing the power button signals software/firmware in the following manner:

•If SCI is enabled, the power button will generate an SCI to the OS.

•The OS will implement the power button policy to allow orderly shutdowns.

•Do not override this with additional hardware.

•If SCI is not enabled:

•Enable the power button to generate an SMI and go directly to soft-off or a supported sleep state.

Intel®440GX AGPset Design Guide

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Contents Intel 440GX AGPset Design GuideIntel440GX AGPset Design Guide Contents 6.4 Dimm Solution With FET SwitchesSystem Bus Clock Layout 6.3 6.5Thermals / Cooling Solutions 20.1 PIIX4E Power And Ground PinsISA and X-Bus Signals 82371EB PIIX4EVoltage Regulator Control Silicon IntelPentiumII Processor LAI IssueFET Switches4 DIMM/FET Design Intel440GX AGPset Platform Reference DesignSolution Space for Single Processor Design Based on Results Example ATX Placement for a UP Pentium II processorExample NLX Placement for a UP Intel Pentium II processor Solution Space for Single Processor Designs With Single-EndIntel Pentium II Processor and Intel 440GX AGPset 100 MHz TablesIntel Pentium II Processor and Intel 440GX AGPset Motherboard Model MAB12,11,90#, MAB14,13,10, 4 DIMMsRevision History Date Revision DescriptionIntel440GX AGPset Design Guide Introduction Page Introduction About This Design GuideReferences Intel Pentium II Processor / Intel 440GX AGPset Overview Intel Pentium II ProcessorIntel 440GX AGPset VCRSystem Bus Interface Dram InterfaceAccelerated Graphics Port Interface PCI Interface Wired for Management InitiativePCI-to-ISA/IDE Xcelerator PIIX4E System ClockingRemote Service Boot InstrumentationVoltage Definitions Power ManagementDesign Recommendations Remote Wake-UpGeneral Design Recommendations Introduction Motherboard Design Page Major Signal Sections 82443GX Top View BGA Quadrant AssignmentATX Form Factor Board Description NLX Form FactorFour Layer Board Stack-up Routing Guidelines Single Processor Design 1 GTL+ Description2 GTL+ Layout Recommendations Single Processor Network Topology and ConditionsSingle Processor Recommended Trace Lengths Recommended Trace Lengths for Single Processor DesignTrace Minimum Length Maximum Length Dual Processor Network Topology and Conditions Dual Processor SystemsSingle Processor Systems-Single-End Termination SET Dual Processor Recommended Trace LengthsSET Trace Length Requirements SET Trace Length RequirementsAdditional Guidelines Minimizing CrosstalkPractical Considerations Design Methodology Performance Requirements 12. GTL+ Design ProcessSimulation Methodology Topology DefinitionPre-Layout Simulation Sensitivity Analysis Recommended 100 MHz System Flight Time SpecsPlacement & Layout Post-Layout SimulationCrosstalk and the Multi-Bit Adjustment Factor ValidationFlight Time Measurement Signal Quality Measurement Edge Guideline @ Processor Edge Spec @ Processor CoreTiming Analysis Term DescriptionTiming Term Intel Pentium II Processor Intel 440GX AGPset 10. Recommended 100 MHz System Timing Parameters11. Recommended 100 MHz System Flight Time Specs Timing Term ValueAGP Layout and Routing Guidelines AGP Connector Up Option Layout GuidelinesConnector 12. Data and Associated Strobe13. Source Synchronous Motherboard Recommendations 14. Control Signal Line Length RecommendationsOn-board AGP Compliant Device Down Option Layout Guidelines WidthSpace Trace Line Length Line Length Matching16. Control Signal Line Length Recommendations Compliant 82443GX Graphics Data Routing Device15. Source Synchronous Motherboard Recommendations 82443GX Memory Subsystem Layout and Routing Guidelines 1 100 MHz 82443GX Memory Array ConsiderationsTo 82443GX MDs & MECCs To DIMM10 DQs To DIMM32 DQs Register Matching the Reference PlanesAdding Additional Decoupling Capacitor Register Data Control ClockMemory Layout & Routing Guidelines Trace Width vs. Trace Spacing18. FET Switch DQ Route Example Switch 16212 Dimm Module82443GX 0.6 0.4 0.6 0.4 Dimm Module 82443GX Dimm Module24. Motherboard Model-DQMB1,5, 4 DIMMs 19. Motherboard Model SRASB#, 4 DIMMs 20. Motherboard Model SCASA#, 4 DIMMs21. Motherboard Model SCASB#, 4 DIMMs 22. Motherboard Model WEA#, 4 DIMMs 23. Motherboard Model WEB#, 4 DIMMs24. Motherboard Model MAA140, 4 DIMMs 25. Motherboard Model MAB12,11,90#, MAB14,13,10, 4 DIMMs 3 4 Dimm Routing Guidelines no FETPCI Bus Routing Guidelines VCC3Decoupling Guidelines Intel 440GX AGPset Platform Host Bridge Controller 492 BGASystem Bus Clock Layout Intel 440GX AGPset Clock Layout RecommendationsClock Routing Spacing 014 018 ClockNet Trace Length Min Max Cap PCI Clock LayoutSdram Clock Layout 440GX Ckbf DlkoAGP Clock Layout Net Trace Length Min Max Card TraceDesign Checklist Page Overview Pull-up and Pull-down Resistor ValuesIntel Pentium II Processor Checklist Slot Connectivity Sheet 1Processor Pin Pin Connection Slot Connectivity Sheet 2 GND & Power Pin Definition Slot Connectivity Sheet 3Vtt VCC3 Reserved NC Vcc Intel Pentium II Processor Signals Intel Pentium II Processor ClocksDesign Checklist Slot 1 Decoupling Capacitors Uni-Processor UP Slot 1 ChecklistDual-Processor DP Slot 1 Checklist Voltage Regulator Module, VRMProcessor Frequency Select Intel 440GX AGPset Clocks1 CK100 100 MHz Clock Synthesizer SEL100/66#Ckbf Sdram 1 to 18 Clock Buffer Gcke and Dclkwr Connection82443GX Host Bridge 1 82443GX InterfaceGX Connectivity Sheet 1 GX Connectivity Sheet 2 GX Connectivity Sheet 3 2 82443GX GTL+ Bus Interface3 82443GX PCI Interface VTTA, VttbSignal Description Register Pulled to ‘0’ Pulled to ‘1’ 4 82443GX AGP InterfaceStrapping Options Sdram Connections 82443GX Pins/Connection Dimm Pins Pin FunctionIntel 440GX AGPset Memory Interface Sdram ConnectivityDimm Solution With FET Switches Registered SdramPIIX4E Connections Signal Names Connection82371EB PIIX4E PIIX4E Connectivity Sheet 1PIIX4E Connectivity Sheet 2 PIIX4E Connectivity Sheet 3 PIIX4E Connectivity Sheet 4 Cabling Signal ResistorIDE Routing Guidelines MotherboardPin32,34 Reset#PDD150 PDA20 IDEPCI Bus Signals PIIX4E Power And Ground PinsPIIX4E PWR & GND 10. Non-PIIX4E PCI Signals ISA SignalsISA and X-Bus Signals 11. Non-PIIX4E ISA SignalsUSB Interface IDE Interface12. Non-PIIX4E IDE Flash Design Considerations Flash DesignDual-Footprint Flash Design PLCC32 to TSOP40 PLCC32 to PSOP44 PDIP32 to TDIP40XD70 13. Flash Vpp Recommendations Write ProtectionSystem and Test Signals Power Management SignalsVCC3 Power Button Implementation Miscellaneous 17 82093AA Ioapic 18.1 Max1617 Temperature Sensor Manageability Devices18.2 LM79 Microprocessor System Hardware Monitor 18.3 82558B LOM Checklist Pin Number Pin Name Resistor Value CommentRequired in both a and B stepping designs Software/BIOS USB and Multi-processor BiosWake On LAN WOL Header Thermals / Cooling Solutions MechanicalsDesign Considerations Electricals Routing and Board Fabrication Layout ChecklistApplications and Add-in Hardware Design ConsiderationDebug Recommendations Page Logic Analyzer Interface LAI Slot 1 Test ToolsDebug/Simulation Tools In-Target Probe ITPBus Functional Model BFM Debug FeaturesIntel Pentium II Processor LAI Issue 4 I/O Buffer Models430 ohm 150 330 ohmKohm 150 ohmDebug Logic Recommendations A20M# 150 330 ohmPICD0# 150 ohm PICD1# Debug Considerations Debug ProceduresDebug Layout Design ConsiderationsDebug Recommendations Third Party Vendors Page GTL+ Bus Slot 1 Terminator Cards Slot 1 ConnectorProcessors Supplier Contact PhoneVoltage Regulator Modules Voltage Regulator ModulesVoltage Regulator Control Silicon Voltage Regulator Control Silicon VendorsIntel 440GX AGPset Power Management ComponentsFET Switches4 DIMM/FET Design Clock DriversOther Processor Components Reference Design Schematics Page Intel 440GX AGPset Platform Reference Design 82443GX Component System bus and Dram Interfaces VRM Power Connectors Front Panel Jumpers

440GX specifications

The Intel 440GX chipset was launched in 1997 as part of Intel's series of chipsets known as the 440 family, and it served as a critical component for various Pentium II and Pentium III-based motherboard architectures. Specifically designed for the second generation of Intel’s processors, the 440GX delivered enhanced performance and supported a range of important technologies that defined PC architectures of its time.

One of the main features of the Intel 440GX was its support for a 100 MHz front-side bus (FSB), which significantly improved data transfer rates between the CPU and the memory subsystem. This advancement allowed the 440GX to accommodate both the original Pentium II processors as well as the later Pentium III chips, providing compatibility and flexibility for system builders and consumers alike.

The 440GX chipset included an integrated AGP (Accelerated Graphics Port) controller, which supported AGP 2x speeds. This enabled high-performance graphics cards to be utilized effectively, delivering many enhanced graphics capabilities for gaming and multimedia applications. The AGP interface was crucial at the time as it offered a dedicated pathway for graphics data, increasing bandwidth compared to traditional PCI slots.

In terms of memory support, the 440GX could address up to 512 MB of SDRAM, allowing systems built with this chipset to run comfortably with sufficient memory for the era’s demanding applications. The memory controller was capable of supporting both single and double-sided DIMMs, which provided versatility in memory configuration for system builders.

Another notable feature of the Intel 440GX was its support for multi-processor configurations through its Dual Processors support feature. This allowed enterprise and workstation computers to leverage the performance advantages of multiple CPUs, making the chipset suitable for business and professional environments where multitasking and high-performance computing were essential.

On the connectivity front, the chipset supported up to six PCI slots, enhancing peripheral device integration and expansion capabilities. It also included integrated IDE controllers, facilitating connections for hard drives and CD-ROM devices.

Overall, the Intel 440GX chipset represented a balanced combination of performance, flexibility, and technology advancements for its time. Its introduction helped establish a foundation for subsequent advancements in PC technology and set the stage for more powerful computing systems in the years to come.
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