Thermal/Mechanical Specifications and Design Guidelines 29
Independent Loading Mechanism (ILM)
4.1.3 Shoulder 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-18 for 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-19 for 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.
Figure 4-2. Back Plate
Die Cut
Insulator
Pierced & Extruded
Thread Features
Assembly
Orientation
Feature
Die Cut
Insulator
Pierced & Extruded
Thread Features
Assembly
Orientation
Feature