Intel 640 User Guide - Page 4

R 5 6 Appendix A 4.2.4 4.2.5 4.2.6 4.2.7 4.2.8 On-Demand Mode 34 System Considerations 34 Operating System and Application Software Considerations 35 On-Die Thermal Diode 35 4.2.7.1 Reading the On-Die Thermal Diode Interface 35 4.2.7.2 Correction Factors for the On-Die Thermal Diode 36 THERMTRIP# Signal 37 4.2.8.1 Cooling System Failure Warning 37 Intel® Thermal/Mechanical Reference Design Information 39 5.1 Intel Validation Criteria for the Reference Design 39 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5 Heatsink Performance Target 39 Acoustics 40 Altitude 40 Reference Heatsink Thermal Validation 41 Fan Performance for Active Heatsink Thermal Solution 41 5.2 Environmental Reliability Testing 42 5.2.1 5.2.2 5.2.3 Structural Reliability Testing 42 5.2.1.1 Random Vibration Test Procedure 42 5.2.1.2 Shock Test Procedure 42 5.2.1.2.1 Recommended Test Sequence 43 5.2.1.2.2 Post-Test Pass Criteria 43 Power Cycling 44 Recommended BIOS/Processor/Memory Test Procedures 44 5.3 Material and Recycling Requirements 44 5.4 Safety Requirements 45 5.5 Geometric Envelope for ATX Intel® Reference Thermal Mechanical Design ...... 45 5.6 ATX Reference Thermal Mechanical Solution for the Intel® Pentium® 4 Processor in the 775-Land LGA Package 46 5.7 Reference Attach Mechanism 48 5.7.1 Structural Design Strategy 48 5.7.2 Mechanical Interface to the Reference Attach Mechanism 49 Acoustic Fan Speed Control 53 6.1 Acoustic Fan Speed Control 53 6.2 Thermal Solution Design 53 6.2.1 Compliance to Thermal Profile 53 6.2.2 Determine Thermistor Set Points 53 6.2.3 Minimum Fan Speed Set Point 54 6.3 Board and System Implementation 55 6.3.1 Choosing Fan Speed Control Settings 55 6.3.1.1 Temperature to begin Fan Acceleration 56 6.3.1.2 Minimum PWM Duty Cycle 58 6.4 Combining Thermistor and Thermal Diode Control 59 6.5 Interaction of Thermal Profile and TCONTROL 59 LGA775 Socket Heatsink Loading 61 A.1 LGA775 Socket Heatsink Considerations 61 A.2 Metric for Heatsink Preload for ATX/µATX Designs Non-Compliant with Intel Reference Design 61 A.2.1 Heatsink Preload Requirement Limitations 61 4 Thermal/Mechanical Design Guide