Intel E2160 Design Guide - Page 18

Intel® CoreTM 2 Duo E6400, E4300, and Intel® Pentium® Dual-Core E2160 Processor-Processor Thermal/Mechanical Information 2.3.2 2.3.3 2.3.4 For the PICMG 1.3 server form factor, it is recommended to use: • The PICMG 1.3 motherboard keep-out footprint definition and height restrictions for enabling components, defined for the platforms designed with the LGA775 socket in Appendix E of this design guide. • The motherboard primary side height constraints are located at http://picmg.org/ specifications.stm. The resulting space available above the motherboard is generally not entirely available for the heatsink. The target height of the heatsink must take into account airflow considerations (for fan performance for example) as well as other design considerations (air duct, etc.). Heatsink Mass With the need to push air cooling to better performance, heatsink solutions tend to grow larger (increase in fin surface) resulting in increased mass. The insertion of highly thermally conductive materials like copper to increase heatsink thermal conduction performance results in even heavier solutions. As mentioned in Section 2.1, the heatsink mass must take into consideration the package and socket load limits, the heatsink attach mechanical capabilities and the mechanical shock and vibration profile targets. Beyond a certain heatsink mass, the cost of developing and implementing a heatsink attach mechanism that can ensure the system integrity under the mechanical shock and vibration profile targets may become prohibitive. Package IHS Flatness The package IHS flatness for the product is specified in the datasheet and can be used as a baseline to predict heatsink performance during the design phase. Intel recommends testing and validating heatsink performance in full mechanical enabling configuration to capture any impact of IHS flatness change due to combined socket and heatsink loading. While socket loading alone may increase the IHS warpage, the heatsink preload redistributes the load on the package and improves the resulting IHS flatness in the enabled state. Thermal Interface Material Thermal interface material application between the processor IHS and the heatsink base is 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 thermal interface material 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 thermal interface material 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. Intel® CoreTM 2 Duo E6400, E4300, and Intel® Pentium® Dual-Core E2160 Processor TDG 18 October 2007 Order Number: 315279 -003US