Intel 440GX manual On-board AGP Compliant Device Down Option Layout Guidelines

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Motherboard Layout and Routing Guidelines

It is always best to reduce the line length mismatch wherever possible to insure added margin. It is also best to separate the traces by as much as possible to reduce the amount of trace to trace coupling.

Table 2-13. Source Synchronous Motherboard Recommendations

Width:Space

Trace

Line Length

Line Length Matching

 

 

 

 

1:1 (Data) / 1:2 (Strobe)

Data / Strobe

1.0 in < line length < 4.5 in

-0.5 in, strobe longest trace

 

 

 

 

1:2

Data / Strobe

1.0 in < line length < 9.5 in

-0.5 in, strobe longest trace

 

 

 

 

The clock lines on the motherboard can couple with other traces. It is recommended that the clock spacing (air gap) be at least two times the trace width to any other traces. It is also strongly recommended that the clock spacing be at least four times the trace width to any strobes.

The clock lines on the motherboard need to be simulated to determine the their proper line length. The motherboard needs to be designed to the type of clock driver that is being used and motherboard trace topology. These clocks need to meet the loading of the receiving device as well as the add-in trace length.

Additionally, control signals less than 8.5 inches can be routed 1:1, while control signals greater than 8.5 inches should be routed 1:2.

Table 2-14. Control Signal Line Length Recommendations

Width:Space

Board

Trace

Line Length

Pull-up Stub Length

 

 

 

 

 

1:1

Motherboard

Control signals

1.0 in < line length < 8.5 in

< 0.5 in (Strobes < 0.1in)

 

 

 

 

 

1:2

Motherboard

Control signals

1.0 in < line length < 10.0 in

< 0.5 in (Strobes < 0.1in)

 

 

 

 

 

1:2 (1:4 to Strobe)

Motherboard

Clock

 

 

 

 

 

 

 

Some of the control signals require pull-up resistors to be installed on the motherboard. AGP signals must be pulled up to VCC3.3 using 8.2K to 10K pull-up resistors (refer to Section 3.5.1, “82443GX Interface” on page 3-10). Pull-up resistors should be discrete resistors, as resistor packs will need longer stub lengths and may break timing. The stub to these pull-up resistors needs to be controlled. The maximum stub length on a strobe trace is < 0.1 inch. The maximum stub trace length on all other traces is < 0.5 inch.

2.8.2On-board AGP Compliant Device (“Down” Option) Layout Guidelines

Routing guidelines for the device ‘down’ option are very similar to those when the device is ‘up’. Some modifications need to be made when placing the graphics device on the motherboard, due to the various trace spacing.

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Intel®440GX AGPset Design Guide

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Contents Intel 440GX AGPset Design GuideIntel440GX AGPset Design Guide Contents Dimm Solution With FET Switches System Bus Clock Layout 6.36.4 6.5PIIX4E Power And Ground Pins ISA and X-Bus SignalsThermals / Cooling Solutions 20.1 82371EB PIIX4EIntelPentiumII Processor LAI Issue FET Switches4 DIMM/FET DesignVoltage Regulator Control Silicon Intel440GX AGPset Platform Reference DesignExample ATX Placement for a UP Pentium II processor Example NLX Placement for a UP Intel Pentium II processorSolution Space for Single Processor Design Based on Results Solution Space for Single Processor Designs With Single-EndTables Intel Pentium II Processor and Intel 440GX AGPsetIntel Pentium II Processor and Intel 440GX AGPset 100 MHz 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 VCRAccelerated Graphics Port Interface System Bus InterfaceDram Interface Wired for Management Initiative PCI-to-ISA/IDE Xcelerator PIIX4EPCI Interface System ClockingRemote Service Boot InstrumentationPower Management Design RecommendationsVoltage Definitions 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 1 GTL+ Description 2 GTL+ Layout RecommendationsSingle Processor Design Single Processor Network Topology and ConditionsTrace Minimum Length Maximum Length Single Processor Recommended Trace LengthsRecommended Trace Lengths for Single Processor Design Dual Processor Systems Single Processor Systems-Single-End Termination SETDual Processor Network Topology and Conditions Dual Processor Recommended Trace LengthsSET Trace Length Requirements SET Trace Length RequirementsPractical Considerations Additional GuidelinesMinimizing Crosstalk Design Methodology Performance Requirements 12. GTL+ Design ProcessTopology Definition Pre-Layout Simulation Sensitivity AnalysisSimulation Methodology Recommended 100 MHz System Flight Time SpecsPlacement & Layout Post-Layout SimulationFlight Time Measurement Crosstalk and the Multi-Bit Adjustment FactorValidation Signal Quality Measurement Edge Guideline @ Processor Edge Spec @ Processor CoreTiming Analysis Term Description10. Recommended 100 MHz System Timing Parameters 11. Recommended 100 MHz System Flight Time SpecsTiming Term Intel Pentium II Processor Intel 440GX AGPset Timing Term ValueAGP Connector Up Option Layout Guidelines ConnectorAGP Layout and Routing Guidelines 12. Data and Associated Strobe14. Control Signal Line Length Recommendations On-board AGP Compliant Device Down Option Layout Guidelines13. Source Synchronous Motherboard Recommendations WidthSpace Trace Line Length Line Length Matching15. Source Synchronous Motherboard Recommendations 16. Control Signal Line Length RecommendationsCompliant 82443GX Graphics Data Routing Device To 82443GX MDs & MECCs To DIMM10 DQs To DIMM32 DQs 82443GX Memory Subsystem Layout and Routing Guidelines1 100 MHz 82443GX Memory Array Considerations Matching the Reference Planes Adding Additional Decoupling CapacitorRegister 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 21. Motherboard Model SCASB#, 4 DIMMs 19. Motherboard Model SRASB#, 4 DIMMs20. Motherboard Model SCASA#, 4 DIMMs 24. Motherboard Model MAA140, 4 DIMMs 22. Motherboard Model WEA#, 4 DIMMs23. Motherboard Model WEB#, 4 DIMMs 3 4 Dimm Routing Guidelines no FET PCI Bus Routing Guidelines25. Motherboard Model MAB12,11,90#, MAB14,13,10, 4 DIMMs VCC3Decoupling Guidelines Intel 440GX AGPset Platform Host Bridge Controller 492 BGAIntel 440GX AGPset Clock Layout Recommendations Clock Routing SpacingSystem Bus Clock Layout 014 018 ClockPCI Clock Layout Sdram Clock LayoutNet Trace Length Min Max Cap 440GX Ckbf DlkoAGP Clock Layout Net Trace Length Min Max Card TraceDesign Checklist Page Overview Pull-up and Pull-down Resistor ValuesProcessor Pin Pin Connection Intel Pentium II Processor ChecklistSlot Connectivity Sheet 1 Slot Connectivity Sheet 2 Vtt VCC3 Reserved NC Vcc GND & Power Pin DefinitionSlot Connectivity Sheet 3 Intel Pentium II Processor Signals Intel Pentium II Processor ClocksDesign Checklist Uni-Processor UP Slot 1 Checklist Dual-Processor DP Slot 1 ChecklistSlot 1 Decoupling Capacitors Voltage Regulator Module, VRMIntel 440GX AGPset Clocks 1 CK100 100 MHz Clock SynthesizerProcessor Frequency Select SEL100/66#Ckbf Sdram 1 to 18 Clock Buffer Gcke and Dclkwr ConnectionGX Connectivity Sheet 1 82443GX Host Bridge1 82443GX Interface GX Connectivity Sheet 2 2 82443GX GTL+ Bus Interface 3 82443GX PCI InterfaceGX Connectivity Sheet 3 VTTA, VttbStrapping Options Signal Description Register Pulled to ‘0’ Pulled to ‘1’4 82443GX AGP Interface 82443GX Pins/Connection Dimm Pins Pin Function Intel 440GX AGPset Memory InterfaceSdram Connections Sdram ConnectivityDimm Solution With FET Switches Registered SdramSignal Names Connection 82371EB PIIX4EPIIX4E Connections PIIX4E Connectivity Sheet 1PIIX4E Connectivity Sheet 2 PIIX4E Connectivity Sheet 3 PIIX4E Connectivity Sheet 4 Signal Resistor IDE Routing GuidelinesCabling MotherboardReset# PDD150 PDA20Pin32,34 IDEPIIX4E PWR & GND PCI Bus SignalsPIIX4E Power And Ground Pins ISA Signals ISA and X-Bus Signals10. Non-PIIX4E PCI Signals 11. Non-PIIX4E ISA Signals12. Non-PIIX4E IDE USB InterfaceIDE Interface Flash Design Dual-Footprint Flash DesignFlash Design Considerations 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 18.2 LM79 Microprocessor System Hardware Monitor 18.1 Max1617 Temperature SensorManageability Devices Required in both a and B stepping designs 18.3 82558B LOM ChecklistPin Number Pin Name Resistor Value Comment Wake On LAN WOL Header Software/BIOSUSB and Multi-processor Bios Design Considerations Thermals / Cooling SolutionsMechanicals Electricals Layout Checklist Applications and Add-in HardwareRouting and Board Fabrication Design ConsiderationDebug Recommendations Page Slot 1 Test Tools Debug/Simulation ToolsLogic Analyzer Interface LAI In-Target Probe ITPDebug Features Intel Pentium II Processor LAI IssueBus Functional Model BFM 4 I/O Buffer Models150 330 ohm Kohm430 ohm 150 ohmPICD0# 150 ohm PICD1# Debug Logic RecommendationsA20M# 150 330 ohm Debug Procedures Debug LayoutDebug Considerations Design ConsiderationsDebug Recommendations Third Party Vendors Page Slot 1 Connector ProcessorsGTL+ Bus Slot 1 Terminator Cards Supplier Contact PhoneVoltage Regulator Modules Voltage Regulator Control SiliconVoltage Regulator Modules Voltage Regulator Control Silicon VendorsPower Management Components FET Switches4 DIMM/FET DesignIntel 440GX AGPset 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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