Intel X5365 Design Guide - Page 85

Quad-Core Intel® Xeon® Processor 5300 Series Thermal/Mechanical Design Guidelines (TMDG)

85

Heatsink Clip Load Methodology

C

Heatsink Clip Load

Methodology

C.1

Overview

This section describes a procedure for measuring the load applied by the heatsink/clip/

fastener assembly on a processor package.

This procedure is recommended to verify the preload is within the design target range

for a design, and in different situations. For example:

•

Heatsink preload for the LGA771 socket.

•

Quantify preload degradation under bake conditions.

Note:

This document reflects the current metrology used by Intel. Intel is continuously

exploring new ways to improve metrology. Updates will be provided later as this

document is revised as appropriate.

C.2

Test Preparation

C.2.1

Heatsink Preparation

Three load cells are assembled into the base of the heatsink under test, in the area

interfacing with the processor Integrated Heat Spreader (IHS), using load cells

equivalent to those listed in

Section C.2.2

.

To install the load cells, machine a pocket in the heatsink base, as shown in

Figure C-1

and

Figure C-2

. The load cells should be distributed evenly, as close as possible to the

pocket walls. Apply wax around the circumference of each load cell and the surface of

the pocket around each cell to maintain the load cells in place during the heatsink

installation on the processor and motherboard.

The depth of the pocket depends on the height of the load cell used for the test. It is

necessary that the load cells protrude out of the heatsink base. However, this

protrusion should be kept minimal, as it will create an additional load offset since the

heatsink base is artificially raised. The measurement load offset depends on the whole

assembly stiffness (i.e. motherboard, clip, fastener, etc.). For example, the Quad-Core

Intel® Xeon® Processor 5300 Series CEK Reference Heatsink Design clip and fasteners

assembly have a stiffness of around 160 N/mm [915 lb/in]. If the resulting protrusion

is 0.038 mm [0.0015”], then a extra load of 6.08 N [1.37 lb] will be created, and will

need to be subtracted from the measured load.

Figure C-3

shows an example using the

Quad-Core Intel® Xeon® Processor 5300 Series CEK Reference Heatsink designed for

the Quad-Core Intel® Xeon® Processor 5300 Series in the 771–land LGA package.

Note:

When optimizing the heatsink pocket depth, the variation of the load cell height should

also be taken into account to make sure that all load cells protrude equally from the

heatsink base. It may be useful to screen the load cells prior to installation to minimize

variation.

Section	Page
1 Introduction	9
1.1 Objective	9
1.2 Scope	9
1.3 References	9
1.4 Definition of Terms	10
2 Thermal/Mechanical Reference Design	13
2.1 Mechanical Requirements	13
2.1.1 Processor Mechanical Parameters	13
2.1.2 Quad-Core Intel® Xeon® Processor 5300 Series Package	14
2.1.3 Quad-Core Intel® Xeon® Processor 5300 Series Considerations	18
2.2 Processor Thermal Parameters and Features	18
2.2.1 Thermal Control Circuit and TDP	18
2.2.2 Digital Thermal Sensor	20
2.2.3 Platform Environmental Control Interface (PECI)	20
2.2.4 Multiple Core Special Considerations	21
2.2.5 Thermal Profile	24
2.2.6 TCONTROL Definition	25
2.2.7 Thermal Profile Concepts for the Quad-Core Intel® Xeon® Processor 5300 Series	26
2.2.8 Performance Targets	28
2.3 Characterizing Cooling Solution Performance Requirements	33
2.3.1 Fan Speed Control	33
2.3.2 Processor Thermal Characterization Parameter Relationships	35
2.3.3 Chassis Thermal Design Considerations	37
2.4 Thermal/Mechanical Reference Design Considerations	37
2.4.1 Heatsink Solutions	37
2.4.2 Thermal Interface Material	38
2.4.3 Summary	39
2.4.4 Assembly Overview of the Intel Reference Thermal Mechanical Design	40
2.4.5 Thermal Solution Performance Characteristics	42
2.4.6 Thermal Profile Adherence	43
2.4.7 Components Overview	47
2.4.8 Boxed Active Thermal Solution for the Quad-Core Intel® Xeon® Processor 5300 Series	51
A 1U Alternative Heatsink Thermal/Mechanical Design	55
A.1 Component Overview	55
A.2 Thermal Solution Performance Characteristics	56
A.3 Thermal Profile Adherence	57
B Mechanical Drawings	59
C Heatsink Clip Load Methodology	85
C.1 Overview	85
C.2 Test Preparation	85
C.2.1 Heatsink Preparation	85
C.2.2 Typical Test Equipment	88
C.2.3 Test Procedure Examples	88
C.2.4 Time-Zero, Room Temperature Preload Measurement	88
C.2.5 Preload Degradation under Bake Conditions	89
D Safety Requirements	91
E Quality and Reliability Requirements	93
E.1 Intel Verification Criteria for the Reference Designs	93
E.1.1 Reference Heatsink Thermal Verification	93
E.1.2 Environmental Reliability Testing	93
E.1.3 Material and Recycling Requirements	95
F Enabled Suppliers Information	97
F.1 Supplier Information	97
F.1.1 Intel Enabled Suppliers	97

Intel X5365 Design Guide - Page 85

C Heatsink Clip Load Methodology, C.1 Overview, C.2 Test Preparation, C.2.1 Heatsink Preparation

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