Intel Core 2 Duo E7300 BX80570E7300 User Manual

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Thermal and Mechanical Design Guidelines  

The primary function of the IHS is to transfer the non-uniform heat distribution from 

the die to the top of the IHS, out of which the heat flux is more uniform and spread 

over a larger surface area (not the entire IHS area). This allows more efficient heat 

transfer out of the package to an attached cooling device. The top surface of the IHS 

is designed to be the interface for contacting a heatsink.  

The IHS also features a step that interfaces with the LGA775 socket load plate, as 

described in LGA775 Socket Mechanical Design Guide. The load from the load plate is 

distributed across two sides of the package onto a step on each side of the IHS. It is 

then distributed by the package across all of the contacts. When correctly actuated, 

the top surface of the IHS is above the load plate allowing proper installation of a 

heatsink on the top surface of the IHS. After actuation of the socket load plate, the 

seating plane of the package is flush with the seating plane of the socket. Package 

movement during socket actuation is along the Z direction (perpendicular to 

substrate) only. Refer to the LGA775 Socket Mechanical Design Guide for further 

information about the LGA775 socket. 

The processor package has mechanical load limits that are specified in the processor 

datasheet. The specified maximum static and dynamic load limits should not be 

exceeded during their respective stress conditions. These include heatsink installation, 

removal, mechanical stress testing, and standard shipping conditions.  

 

When a compressive static load is necessary to ensure thermal performance of the 

thermal interface material between the heatsink base and the IHS, it should not 

exceed the corresponding specification given in the processor datasheet. 

 

When a compressive static load is necessary to ensure mechanical performance, it 

should remain in the minimum/maximum range specified in the processor 

datasheet  

 

The heatsink mass can also generate additional dynamic compressive load to the 

package during a mechanical shock event. Amplification factors due to the impact 

force during shock must be taken into account in dynamic load calculations. The 

total combination of dynamic and static compressive load should not exceed the 

processor datasheet compressive dynamic load specification during a vertical 

shock. For example, with a 0.550 kg [1.2 lb] heatsink, an acceleration of 50G 

during an 11 ms trapezoidal shock with an amplification factor of 2 results in 

approximately a 539 N [117 lbf] dynamic load on the processor package. If a  

178 N [40 lbf] static load is also applied on the heatsink for thermal performance 

of the thermal interface material the processor package could see up to a 717 N 

 [156 lbf]. The calculation for the thermal solution of interest should be compared 

to the processor datasheet specification. 

No portion of the substrate should be used as a load- bearing surface. 

Finally, the processor datasheet provides package handling guidelines in terms of 

maximum recommended shear, tensile and torque loads for the processor IHS relative 

to a fixed substrate. These recommendations should be followed in particular for 

heatsink removal operations.