Independent Loading Mechanism (ILM)

Figure 4-2. Back Plate

Assembly

Die Cut

Orientation

Insulator

Feature

 

Pierced & Extruded

Thread Features

4.1.3Shoulder Screw and Fasteners Design Overview

The shoulder screw is fabricated from carbonized steel rod. The shoulder height and diameter are integral to the mechanical performance of the ILM. The diameter provides alignment of the load plate. The height of the shoulder ensures the proper loading of the IHS to seat the processor on the socket contacts. The design assumes the shoulder screw has a minimum yield strength of 235 MPa.

A dimensioned drawing of the shoulder screw is available for local sourcing of this component. Please refer to Figure B-18for the custom 6-32 thread shoulder screw drawing.

The standard fasteners can be sourced locally. The design assumes this fastener has a minimum yield strength of 235 MPa. Please refer to Figure B-19for the standard 6-32 thread fasteners drawing.

The screws for Server ILM are different from Desktop design. The length of Server ILM screws are shorter than the Desktop screw length to satisfy Server secondary-side clearance limitation. Server ILM back plate to use black nickel plated screws, whereas desktop ILM back plate to use clear plated screws. Unique part numbers, please refer to Appendix A.

Note: The reference design incorporates a T-20 Torx head fastener. The Torx head fastener was chosen to ensure end users do not inadvertently remove the ILM assembly and for consistency with the LGA1366 socket ILM.

Thermal/Mechanical Specifications and Design Guidelines

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