Intel 5400 Series manual Thermal Interface Material, Summary

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Thermal/Mechanical Reference Design

2.5.2Thermal Interface Material

TIM application between the processor IHS and the heatsink base is generally required to improve thermal conduction from the IHS to the heatsink. Many thermal interface materials can be pre-applied to the heatsink base prior to shipment from the heatsink supplier and allow direct heatsink attach, without the need for a separate TIM dispense or attach process in the final assembly factory.

All thermal interface materials should be sized and positioned on the heatsink base in a way that ensures the entire processor IHS area is covered. It is important to compensate for heatsink-to-processor attach positional alignment when selecting the proper TIM size.

When pre-applied material is used, it is recommended to have a protective application tape over it. This tape must be removed prior to heatsink installation.

The TIM performance is susceptible to degradation (i.e. grease breakdown) during the useful life of the processor due to the temperature cycling phenomena. For this reason, the measured TCASE value of a given processor can decrease over time depending on the type of TIM material.

Refer to Section 2.5.7.2 for information on the TIM used in the Intel reference heatsink solution.

2.5.3Summary

In summary, considerations in heatsink design include:

•The local ambient temperature TLA at the heatsink, airflow (CFM), the power being dissipated by the processor, and the corresponding maximum TCASE temperature. These parameters are usually combined in a single lump cooling performance

parameter, ΨCA (case to air thermal characterization parameter). More information on the definition and the use of ΨCA is given in Section 2.5 and Section 2.4.2.

•Heatsink interface (to IHS) surface characteristics, including flatness and roughness.

•The performance of the TIM used between the heatsink and the IHS.

•Surface area of the heatsink.

•Heatsink material and technology.

•Development of airflow entering and within the heatsink area.

•Physical volumetric constraints placed by the system.

•Integrated package/socket stackup height information is provided in the LGA771 Socket Mechanical Design Guide.

38	Quad-Core Intel® Xeon® Processor 5400 Series TMDG

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Contents Quad-Core Intel Xeon Processor 5400 Series Thermal/Mechanical Design GuidelinesQuad-Core Intel Xeon Processor 5400 Series Tmdg Contents Figures Preload Test Configuration Tables Reference Revision Description Date Number Initial release of the documentQuad-Core Intel Xeon Processor 5400 Series Tmdg References ObjectiveScope Term Description Definition of TermsTerms and Descriptions Sheet 1 Terms and Descriptions Sheet 2 TDPIntroduction Processor Mechanical Parameters Table Mechanical RequirementsProcessor Mechanical Parameters Parameter Minimum Maximum UnitQuad-Core Intel Xeon Processor 5400 Series Package Thermal/Mechanical Reference Design Thermal/Mechanical Reference Design Thermal/Mechanical Reference Design Quad-Core Intel Xeon Processor 5400 Series Considerations Processor Thermal Parameters and Features Thermal Control Circuit and TDPDigital Thermal Sensor Multiple Digital Thermal Sensor Operation Platform Environmental Control Interface PeciMultiple Core Special Considerations Heatpipe Orientation for Multiple Core Processors Thermal Monitor for Multiple Core ProductsPROCHOT#, THERMTRIP#, and FORCEPR# Processor Input Processor OutputProcessor Core Geometric Center Dimensions Feature DimensionThermal Profile Equation 2-1.y = ax + bTcontrol Definition Equation 2-2.TCONTROL= -TOFFSETTcontrol and Thermal Profile Interaction Thermal Profile B Performance Targets Thermal/Mechanical Reference Design Thermal/Mechanical Reference Design 1U CEK, Thermal Profile B Parameter Maximum Unit2U+ CEK, Thermal Profile a 1U Alternative Heatsink Fan Fail GuidelinesSea-Level Characterizing Cooling Solution Performance Requirements Fan Speed ControlEquation 2-3.ΨCA= Tcase TLA / TDP Processor Thermal Characterization Parameter RelationshipsFan Speed Control, Tcontrol and DTS Relationship Condition FSC SchemeExample Equation 2-4.ΨCA= ΨCS + ΨSAEquation 2-5.ΨCA= Tcase TLA / TDP = 68 45 / 85 = 0.27 C/W Chassis Thermal Design ConsiderationsChassis Thermal Design Capabilities and Improvements Equation 2-6.ΨSA= ΨCA − ΨCS = 0.27 − 0.05 = 0.22 C/WHeatsink Design Considerations Heatsink SolutionsThermal/Mechanical Reference Design Considerations Thermal Interface Material SummaryAssembly Drawing Geometric EnvelopeStructural Considerations of CEK Thermal Solution Performance Characteristics 17 U+ CEK Heatsink Thermal PerformanceThermal Profile Adherence Equation 2-8.y = 0.187*X +=0.187* X +40 Equation 2-9.y = 0.246*X +1UCEKReference Solution Equation 2-10.y = 0.246*X +Components Overview Heatsink with Captive Screws and Standoffs22. Isometric View of the 2U+ CEK Heatsink Thermal Interface Material TIM CEK Heatsink Thermal Mechanical CharacteristicsRecommended Thermal Grease Dispense Weight Processor Minimum Maximum UnitsCEK Spring 24. CEK Spring Isometric ViewThermal/Mechanical Reference Design Description Min Typ Max Unit Steady Startup Fan Power SupplyFan Specifications Boxed 4-wire PWM/DTS Heatsink Solution Boxed Processor Contents Systems Considerations Associated with the Active CEKThermal/Mechanical Reference Design Component Overview Figure A-1. Isometric View of the 1U Alternative HeatsinkEquation A-1. y = 0.331*x + Thermal Solution Performance CharactericsThermal Profile Adherence = Processor power value W 1U Alternative Heatsink Thermal/Mechanical Design Table B-1. Mechanical Drawing List Drawing DescriptionFigure B-1 2U CEK Heatsink Sheet 1 Figure B-2 2U CEK Heatsink Sheet 2 Figure B-3 U CEK Heatsink Sheet 3 Figure B-4 2U CEK Heatsink Sheet 4 Figure B-5. CEK Spring Sheet 1 Figure B-6. CEK Spring Sheet 2 Figure B-7. CEK Spring Sheet 3 Mechanical Drawings Mechanical Drawings Mechanical Drawings Mechanical Drawings Mechanical Drawings Mechanical Drawings Figure B-14 U CEK Heatsink Sheet 1 Figure B-15 U CEK Heatsink Sheet 2 Figure B-16 U CEK Heatsink Sheet 3 Figure B-17 U CEK Heatsink Sheet 4 Figure B-18. Active CEK Thermal Solution Volumetric Sheet 1 Figure B-19. Active CEK Thermal Solution Volumetric Sheet 2 Figure B-20. Active CEK Thermal Solution Volumetric Sheet 3 Figure B-21 U Alternative Heatsink 1 Figure B-22 U Alternative Heatsink 2 Figure B-23 U Alternative Heatsink 3 Figure B-24 U Alternative Heatsink 4 Mechanical Drawings Heatsink Preparation OverviewTest Preparation Alternate Heatsink Sample Preparation Figure C-3. Preload Test Configuration Typical Test Equipment Test Procedure ExamplesTime-Zero, Room Temperature Preload Measurement Table C-1. Typical Test EquipmentPreload Degradation under Bake Conditions Heatsink Clip Load Methodology Safety Requirements Safety Requirements Intel Verification Criteria for the Reference Designs Environmental Reliability TestingStructural Reliability Testing Reference Heatsink Thermal VerificationTable E-1 Use Conditions Environment 2.2 Recommended Test SequencePost-Test Pass Criteria Recommended BIOS/Processor/Memory Test Procedures Material and Recycling RequirementsQuality and Reliability Requirements Intel Enabled Suppliers Supplier InformationAdditional Suppliers For 1U2U Heatsink Alternative CEK Copper Fin Alternative CEK Copper Fin Enabled Suppliers Information 100 Quad-Core Intel Xeon Processor 5400 Series Tmdg