Intel X5550 - Quad Core Xeon Guide

Reference Number: 321323-002
Intel® Xeon® Processor 5500/5600
Series
Thermal/Mechanical Design Guide
March 2010

2 Thermal/Mechanical Design Guide
INFORMATION IN THIS DOCUMENT IS PROVIDED IN CONNECTION WITH INTEL® PRODUCTS. NO LICENSE, EXPRESS OR IMPLIED,
BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THIS DOCUMENT. EXCEPT AS
PROVIDED IN INTEL'S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, INTEL ASSUMES NO LIABILITY WHATSOEVER,
AND INTEL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY, RELATING TO SALE AND/OR USE OF INTEL PRODUCTS INCLUDING
LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY
PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT. Intel products are not intended for use in medical, life saving, or
life sustaining applications.
Intel may make changes to specifications and product descriptions at any time, without notice.
Designers must not rely on the absence or characteristics of any features or instructions marked “reserved” or “undefined.” Intel
reserves these for future definition and shall have no responsibility whatsoever for conflicts or incompatibilities arising from future
changes to them.
The Intel® Xeon® processor 5500 series, 5600 series and LGA1366 socket may contain design defects or errors known as errata
which may cause the product to deviate from published specifications. Current characterized errata are available on request.
Contact your local Intel sales office or your distributor to obtain the latest specifications and before placing your product order.
Intel processor numbers are not a measure of performance. Processor numbers differentiate features within each processor family,
not across different processor families. See http://www.intel.com/products/processor_number for details. Over time processor
numbers will increment based on changes in clock, speed, cache, FSB, or other features, and increments are not intended to
represent proportional or quantitative increases in any particular feature. Current roadmap processor number progression is not
necessarily representative of future roadmaps. See www.intel.com/products/processor_number for details.
Intel® Turbo Boost Technology requires a PC with a processor with Intel Turbo Boost Technology capability. Intel Turbo Boost
Technology performance varies depending on hardware, software and overall system configuration. Check with your PC
manufacturer on whether your system delivers Intel Turbo Boost Technology. For more information, see www.intel.com.
Intel, Xeon, and the Intel logo are trademarks of Intel Corporation in the U.S and other countries.
* Other brands and names may be claimed as the property of others.
Copyright © 2009, Intel Corporation.

Thermal/Mechanical Design Guide 3
Contents
1 Introduction ..............................................................................................................9
1.1 References ....................................................................................................... 10
1.2 Definition of Terms............................................................................................ 10
2 LGA1366 Socket ......................................................................................................13
2.1 Board Layout.................................................................................................... 15
2.2 Attachment to Motherboard ................................................................................ 16
2.3 Socket Components...........................................................................................16
2.3.1 Socket Body Housing.............................................................................. 16
2.3.2 Solder Balls...........................................................................................16
2.3.3 Contacts ............................................................................................... 17
2.3.4 Pick and Place Cover............................................................................... 17
2.4 Package Installation / Removal ...........................................................................18
2.4.1 Socket Standoffs and Package Seating Plane.............................................. 18
2.5 Durability......................................................................................................... 19
2.6 Markings.......................................................................................................... 19
2.7 Component Insertion Forces ............................................................................... 19
2.8 Socket Size ...................................................................................................... 19
2.9 LGA1366 Socket NCTF Solder Joints..................................................................... 20
3 Independent Loading Mechanism (ILM)................................................................... 21
3.1 Design Concept................................................................................................. 21
3.1.1 ILM Cover Assembly Design Overview ....................................................... 21
3.1.2 ILM Back Plate Design Overview............................................................... 22
3.2 Assembly of ILM to a Motherboard....................................................................... 23
4 LGA1366 Socket and ILM Electrical, Mechanical, and Environmental Specifications . 27
4.1 Component Mass............................................................................................... 27
4.2 Package/Socket Stackup Height .......................................................................... 27
4.3 Socket Maximum Temperature............................................................................ 27
4.4 Loading Specifications........................................................................................ 28
4.5 Electrical Requirements...................................................................................... 28
4.6 Environmental Requirements ..............................................................................29
5 Thermal Solutions ...................................................................................................31
5.1 Performance Targets.......................................................................................... 31
5.1.1 25.5 mm Tall Heatsink............................................................................ 32
5.2 Heat Pipe Considerations.................................................................................... 33
5.3 Assembly ......................................................................................................... 34
5.3.1 Thermal Interface Material (TIM).............................................................. 35
5.4 Structural Considerations ...................................................................................35
5.5 Thermal Design................................................................................................. 35
5.5.1 Thermal Characterization Parameter ......................................................... 35
5.5.2 Dual Thermal Profile ............................................................................... 36
5.6 Thermal Features..............................................................................................37
5.6.1 Fan Speed Control.................................................................................. 37
5.6.2 PECI Averaging and Catastrophic Thermal Management...............................38
5.6.3 Intel® Turbo Boost Technology................................................................ 39
5.7 Thermal Guidance ............................................................................................. 39
5.7.1 Thermal Excursion Power for Processors with Dual Thermal Profile................ 39
5.7.2 Thermal Excursion Power for Processors with Single Thermal Profile..............40
5.7.3 Absolute Processor Temperature .............................................................. 40
6 Quality and Reliability Requirements.......................................................................41
6.1 Test Conditions................................................................................................. 41

4 Thermal/Mechanical Design Guide
6.2 Intel Reference Component Validation ..................................................................43
6.2.1 Board Functional Test Sequence ...............................................................43
6.2.2 Post-Test Pass Criteria.............................................................................43
6.2.3 Recommended BIOS/Processor/Memory Test Procedures .............................44
6.3 Material and Recycling Requirements....................................................................44
A Component Suppliers...............................................................................................45
A.1 Intel Enabled Supplier Information.......................................................................45
A.1.1 Intel Reference Thermal Solution ..............................................................45
A.1.2 Intel Collaboration Thermal Solution..........................................................45
A.1.3 Alternative Thermal Solution ....................................................................46
A.1.4 Socket and ILM Components ....................................................................47
B Mechanical Drawings ...............................................................................................49
C Socket Mechanical Drawings....................................................................................83
D Heatsink Load Metrology..........................................................................................89
E Embedded Thermal Solutions...................................................................................91
E.1 Performance Targets..........................................................................................91
E.2 Thermal Design Guidelines..................................................................................92
E.2.1 NEBS Thermal Profile ..............................................................................92
E.2.2 Custom Heat Sinks For UP ATCA ...............................................................93
E.3 Mechanical Drawings and Supplier Information ......................................................96
F Processor Installation Tool ....................................................................................101
Figures
1-1 Intel® Xeon® 5500 Platform Socket Stack............................................................. 9
2-1 LGA1366 Socket with Pick and Place Cover Removed..............................................13
2-2 LGA1366 Socket Contact Numbering (Top View of Socket) ......................................14
2-3 LGA1366 Socket Land Pattern (Top View of Board).................................................15
2-4 Attachment to Motherboard.................................................................................16
2-5 Pick and Place Cover ..........................................................................................17
2-6 Package Installation / Removal Features...............................................................18
2-7 LGA1366 NCTF Solder Joints ...............................................................................20
3-1 ILM Cover Assembly...........................................................................................22
3-2 Back Plate ........................................................................................................23
3-3 ILM Assembly....................................................................................................24
3-4 Pin1 and ILM Lever ............................................................................................25
4-1 Flow Chart of Knowledge-Based Reliability Evaluation Methodology...........................30
5-1 Best-fit Equations ..............................................................................................32
5-2 TTV Die Size and Orientation...............................................................................33
5-3 1U Reference Heatsink Assembly .........................................................................34
5-4 Processor Thermal Characterization Parameter Relationships ...................................36
5-5 Dual Thermal Profile...........................................................................................37
6-1 Example Thermal Cycle - Actual profile will vary ....................................................43
B-1 Board Keepin / Keepout Zones (Sheet 1 of 4)........................................................50
B-2 Board Keepin / Keepout Zones (Sheet 2 of 4)........................................................51
B-3 Board Keepin / Keepout Zones (Sheet 3 of 4)........................................................52
B-4 Board Keepin / Keepout Zones (Sheet 4 of 4)........................................................53
B-5 1U Reference Heatsink Assembly (Sheet 1 of 2).....................................................54
B-6 1U Reference Heatsink Assembly (Sheet 2 of 2).....................................................55
B-7 1U Reference Heatsink Fin and Base (Sheet 1 of 2) ................................................56
B-8 1U Reference Heatsink Fin and Base (Sheet 2 of 2) ................................................57

Thermal/Mechanical Design Guide 5
B-9 Heatsink Shoulder Screw (1U, 2U and Tower) ....................................................... 58
B-10 Heatsink Compression Spring (1U, 2U and Tower) ................................................. 59
B-11 Heatsink Retaining Ring (1U, 2U and Tower)......................................................... 60
B-12 Heatsink Load Cup (1U, 2U and Tower) ................................................................ 61
B-13 2U Collaborative Heatsink Assembly (Sheet 1 of 2)................................................ 62
B-14 2U Collaborative Heatsink Assembly (Sheet 2 of 2)................................................ 63
B-15 2U Collaborative Heatsink Volumetric (Sheet 1 of 2) .............................................. 64
B-16 2U Collaborative Heatsink Volumetric (Sheet 2 of 2) .............................................. 65
B-17 Tower Collaborative Heatsink Assembly (Sheet 1 of 2) ........................................... 66
B-18 Tower Collaborative Heatsink Assembly (Sheet 2 of 2) ........................................... 67
B-19 Tower Collaborative Heatsink Volumetric (Sheet 1 of 2).......................................... 68
B-20 Tower Collaborative Heatsink Volumetric (Sheet 2 of 2).......................................... 69
B-21 1U Reference Heatsink Assembly with TIM (Sheet 1 of 2) ....................................... 70
B-22 1U Reference Heatsink Assembly with TIM (Sheet 2 of 2) ....................................... 71
B-23 2U Reference Heatsink Assembly with TIM (Sheet 1 of 2) ....................................... 72
B-24 2U Reference Heatsink Assembly with TIM (Sheet 2 of 2) ....................................... 73
B-25 Tower Reference Heatsink Assembly with TIM (Sheet 1 of 2)...................................74
B-26 Tower Reference Heatsink Assembly with TIM (Sheet 2 of 2)...................................75
B-27 25.5mm Reference Heatsink Assembly (Sheet 1 of 2) ............................................ 76
B-28 25.5mm Reference Heatsink Assembly (Sheet 2 of 2) ............................................ 77
B-29 25.5mm Reference Heatsink Fin and Base (Sheet 1 of 2)........................................ 78
B-30 25.5mm Reference Heatsink Fin and Base (Sheet 2 of 2)........................................ 79
B-31 25.5mm Reference Heatsink Assembly with TIM (Sheet 1 of 2)................................ 80
B-32 25.5mm Reference Heatsink Assembly with TIM (Sheet 2 of 2)................................ 81
C-1 Socket Mechanical Drawing (Sheet 1 of 4) ............................................................ 84
C-2 Socket Mechanical Drawing (Sheet 2 of 4) ............................................................ 85
C-3 Socket Mechanical Drawing (Sheet 3 of 4) ............................................................ 86
C-4 Socket Mechanical Drawing (Sheet 4 of 4) ............................................................ 87
D-1 Intel Xeon Processor 5500 Series Load Cell Fixture ................................................ 90
E-1 ATCA Heatsink Performance Curves ..................................................................... 92
E-2 NEBS Thermal Profile......................................................................................... 93
E-3 UP ATCA Thermal Solution.................................................................................. 94
E-4 UP ATCA System Layout.....................................................................................94
E-5 UP ATCA Heat Sink Drawing................................................................................ 95
E-6 ATCA Reference Heat Sink Assembly (Sheet 1 of 2) ............................................... 97
E-7 ATCA Reference Heat Sink Assembly (Sheet 2 of 2) ............................................... 98
E-8 ATCA Reference Heatsink Fin and Base (Sheet 1 of 2) ............................................ 99
E-9 ATCA Reference Heatsink Fin and Base (Sheet 2 of 2) .......................................... 100
F-1 Processor Installation Tool................................................................................ 102

6 Thermal/Mechanical Design Guide
Tables
1-1 Reference Documents.........................................................................................10
1-2 Terms and Descriptions ......................................................................................10
4-1 Socket Component Mass.....................................................................................27
4-2 1366-land Package and LGA1366 Socket Stackup Height ........................................27
4-3 Socket and ILM Mechanical Specifications .............................................................28
4-4 Electrical Requirements for LGA1366 Socket..........................................................29
5-1 Boundary Conditions and Performance Targets for
Intel® Xeon® Processor 5500 Series ...................................................................31
5-2 Boundary Conditions and Performance Targets for
Intel Xeon processor 5600 series .........................................................................31
5-3 Performance Expectations for Intel Xeon Processor 5500
Series with 25.5 mm Tall Heatsink .......................................................................32
5-4 Fan Speed Control, TCONTROL and DTS Relationship..............................................37
5-5 TCONTROL Guidance.............................................................................................38
6-1 Heatsink Test Conditions and Qualification Criteria .................................................41
A-1 Suppliers for the Intel Reference Thermal Solution .................................................45
A-2 Suppliers for the Intel Collaboration Thermal Solution.............................................46
A-3 Suppliers for the Alternative Thermal Solution .......................................................46
A-4 LGA1366 Socket and ILM Components..................................................................47
B-1 Mechanical Drawing List......................................................................................49
C-1 Mechanical Drawing List......................................................................................83
E-1 Boundary Conditions and Performance Targets for
Intel® Xeon® Processor 5500 Series ...................................................................91
E-2 Boundary Conditions and Performance Targets for
Intel® Xeon® Processor 5600 Series ...................................................................91
E-3 Embedded Heatsink Component Suppliers.............................................................96
E-4 Mechanical Drawings List ....................................................................................96

Thermal/Mechanical Design Guide 7
Revision History
§
Document
Number Revision Number Description Revision Date
321323 001 Public Release March 2009
321323 002
Updates / additions in this revision include:
• Changed to reflect addition of Intel® Xeon® Processor 5600 Series
• Figure 1-1: replaced to show ILM load plate with cut out
• Table 1-1: Updated References
• Figures 2-4, 2-5: replaced to show ILM load plate with cut out
• Section 2.3.4: Added Pick_and_Place_Removal_Tool
• Section 3.1.1: fasteners are low carbon steel
• Figures 3-1, 3-3, 3-4: replaced to show ILM load plate with cut out
• Figure 3-2: replaced to show studs without knurled feature
• Section 3.2: Changed torque from 8 ± 2 to 9 ± 1 inch-pounds
• Table 4-3: min static load changed from 106 lbf to 100 lbf
• Table 4-3: clarified Parameter as Target Pick and Place Cover allowable removal
force and updated the force associated with it
• Table 5-1: Changed dP for 2U and Tower heatsink
• Table 5-2: Added Boundary Conditions and Performance Targets for Intel®
Xeon® Processor 5600 Series
• Figure 5-1: replaced curves for 1U with equations for 1U, 2U and Tower
• Table 5-3: specified for Intel® Xeon® Processor 5500 Series Processors
• Table 5-3: updated PSIca and dP values
• Figure 5-3: replaced to show ILM load plate with cut out
• Section 5.3: added Fastener sequencing statement (may mitigate against cross
threading).
• Table 5-5: added Tcontrol Guidance for Intel® Xeon® Processor 5600 Series
• Section 5.7: added Thermal Excursion for Intel® Xeon® Processor 5600 Series
• Table 6-1: added reference to Table 5-2 for Intel® Xeon® Processor 5600 Series
• Appendix A: added heatsink info for Intel® Xeon® Processor 5600 Series
• Table A-4, A-5: updated supplier info
• Appendix B: Added Figures B-27 to B-32 for 25.5mm heatsink
• Table E-1: updated PSIca for 60W
• Table E-2: added Boundary Conditions and Performance Targets for Intel®
Xeon® Processor 5600 Series
March 2010

8 Thermal/Mechanical Design Guide

Thermal/Mechanical Design Guide 9
Introduction
1Introduction
This document provides guidelines for the design of thermal and mechanical solutions
for 2-socket server and 2-socket Workstation processors listed in the Intel® Xeon®
Processor 5500 Series Datasheet, Volume 1 and in the Intel® Xeon® Processor 5600
Series Datasheet, Volume 1. The components described in this document include:
• The processor thermal solution (heatsink) and associated retention hardware.
• The LGA1366 socket and the Independent Loading Mechanism (ILM) and back
plate.
Processors in 1-socket Workstation platforms are covered in the Intel®Core™ i7-900
Desktop Processor Extreme Edition Series and Intel®Core™ i7-900 Desktop Processor
Series, Intel®Xeon®Processor 3500 Series and LGA1366 Socket Thermal / Mechanical
Design Guide.
The goals of this document are:
• To assist board and system thermal mechanical designers.
• To assist designers and suppliers of processor heatsinks.
Thermal profiles and other processor specifications are provided in the Datasheet.
Figure 1-1. Intel® Xeon® 5500 Platform Socket Stack

Introduction
10 Thermal/Mechanical Design Guide
1.1 References
Material and concepts available in the following documents may be beneficial when
reading this document.
Notes:
1. Document numbers indicated in Location column are subject to change. See the appropriate Electronic
Design Kit (EDK) for the most up-to-date Document number.
2. Available at http://www.blauer-engel.de
3. Available at http://ssiforum.org/
1.2 Definition of Terms
Table 1-1. Reference Documents
Document Location Notes
European Blue Angel Recycling Standards 2
Intel® Xeon® Processor 5500 Series Datasheet, Volume 1 321321 1
Intel® Xeon® Processor 5600 Series Datasheet, Volume 1 323369 1
Intel® Xeon® Processor 5500 Series Mechanical Model 321326 1
Intel® Xeon® Processor 5500 Series Thermal Model 321327 1
Entry-level Electronics Bay Specification 3
Table 1-2. Terms and Descriptions (Sheet 1 of 2)
Term Description
Bypass Bypass is the area between a passive heatsink and any object that can act to form a
duct. For this example, it can be expressed as a dimension away from the outside
dimension of the fins to the nearest surface.
DTS Digital Thermal Sensor reports a relative die temperature as an offset from TCC
activation temperature.
FSC Fan Speed Control
IHS Integrated Heat Spreader: a component of the processor package used to enhance the
thermal performance of the package. Component thermal solutions interface with the
processor at the IHS surface.
ILM Independent Loading Mechanism provides the force needed to seat the 1366-LGA land
package onto the socket contacts.
LGA1366 socket The processor mates with the system board through this surface mount, 1366-contact
socket.
PECI The Platform Environment Control Interface (PECI) is a one-wire interface that provides
a communication channel between Intel processor and chipset components to external
monitoring devices.
CA Case-to-ambient thermal characterization parameter (psi). A measure of thermal
solution performance using total package power. Defined as (TCASE – TLA) / Total
Package Power. Heat source should always be specified for measurements.
CS Case-to-sink thermal characterization parameter. A measure of thermal interface
material performance using total package power. Defined as (TCASE – TS) / Total
Package Power.
SA Sink-to-ambient thermal characterization parameter. A measure of heatsink thermal
performance using total package power. Defined as (TS– TLA) / Total Package Power.
TCASE The case temperature of the processor measured at the geometric center of the topside
of the IHS.
TCASE_MAX The maximum case temperature as specified in a component specification.

Thermal/Mechanical Design Guide 11
Introduction
§
TCC Thermal Control Circuit: Thermal monitor uses the TCC to reduce the die temperature
by using clock modulation and/or operating frequency and input voltage adjustment
when the die temperature is very near its operating limits.
TCONTROL TCONTROL is a static value below TCC activation used as a trigger point for fan speed
control.
TDP Thermal Design Power: Thermal solution should be designed to dissipate this target
power level. TDP is not the maximum power that the processor can dissipate.
Thermal Monitor A power reduction feature designed to decrease temperature after the processor has
reached its maximum operating temperature.
Thermal Profile Line that defines case temperature specification of a processor at a given power level.
TIM Thermal Interface Material: The thermally conductive compound between the heatsink
and the processor case. This material fills the air gaps and voids, and enhances the
transfer of the heat from the processor case to the heatsink.
TLA The measured ambient temperature locally surrounding the processor. The ambient
temperature should be measured just upstream of a passive heatsink or at the fan inlet
for an active heatsink.
TSA The system ambient air temperature external to a system chassis. This temperature is
usually measured at the chassis air inlets.
U A unit of measure used to define server rack spacing height. 1U is equal to 1.75 in, 2U
equals 3.50 in, etc.
Table 1-2. Terms and Descriptions (Sheet 2 of 2)
Term Description

Introduction
12 Thermal/Mechanical Design Guide

Thermal/Mechanical Design Guide 13
LGA1366 Socket
2LGA1366 Socket
This chapter describes a surface mount, LGA (Land Grid Array) socket intended for
processors in the Intel® Xeon® 5500 Platform. The socket provides I/O, power and
ground contacts. The socket contains 1366 contacts arrayed about a cavity in the
center of the socket with lead-free solder balls for surface mounting on the
motherboard.
The socket has 1366 contacts with 1.016 mm X 1.016 mm pitch (X by Y) in a
43x41 grid array with 21x17 grid depopulation in the center of the array and selective
depopulation elsewhere.
The socket must be compatible with the package (processor) and the Independent
Loading Mechanism (ILM). The design includes a back plate which is integral to having
a uniform load on the socket solder joints. Socket loading specifications are listed in
Chapter 4.
Figure 2-1. LGA1366 Socket with Pick and Place Cover Removed
socket
cavity
package socket
cavity
package

LGA1366 Socket
14 Thermal/Mechanical Design Guide
Figure 2-2. LGA1366 Socket Contact Numbering (Top View of Socket)

Thermal/Mechanical Design Guide 15
LGA1366 Socket
2.1 Board Layout
The land pattern for the LGA1366 socket is 40 mils X 40 mils (X by Y), and the pad size
is 18 mils. Note that there is no round-off (conversion) error between socket pitch
(1.016 mm) and board pitch (40 mil) as these values are equivalent.
Figure 2-3. LGA1366 Socket Land Pattern (Top View of Board)
A C E G J L N R U W AA AC AE AG AJ AL AN AR AU AW BA
B D F H K M P T V Y AB AD AF AH AK AM AP AT AV AY
1
3
7
5
9
11
15
13
17
19
23
21
25
27
31
29
1
3
7
5
9
11
15
13
17
19
23
21
25
27
31
29
2
8
4
6
10
16
12
14
18
24
20
22
26
32
28
30
2
8
4
6
10
16
12
14
18
24
20
22
26
32
28
30
16
12
15
13
14
17
18
24
20
19
23
21
22
25
26
32
28
27
31
29
30
33
34
40
36
35
39
37
38
41
42
43
B D F H K M P T V Y AB AD AF AH AK AM AP AT AV AY
A C E G J L N R U W AA AC AE AG AJ AL AN AR AU AW BA

LGA1366 Socket
16 Thermal/Mechanical Design Guide
2.2 Attachment to Motherboard
The socket is attached to the motherboard by 1366 solder balls. There are no additional
external methods (that is, screw, extra solder, adhesive, and so on) to attach the
socket.
As indicated in Figure 2-4, the Independent Loading Mechanism (ILM) is not present
during the attach (reflow) process.
2.3 Socket Components
The socket has two main components, the socket body and Pick and Place (PnP) cover,
and is delivered as a single integral assembly. Refer to Appendix C for detailed
drawings.
2.3.1 Socket Body Housing
The housing material is thermoplastic or equivalent with UL 94 V-0 flame rating capable
of withstanding 260 °C for 40 seconds (typical reflow/rework). The socket coefficient of
thermal expansion (in the XY plane), and creep properties, must be such that the
integrity of the socket is maintained for the conditions listed in the LGA1366 Socket
Validation Reports.
The color of the housing will be dark as compared to the solder balls to provide the
contrast needed for pick and place vision systems.
2.3.2 Solder Balls
A total of 1366 solder balls corresponding to the contacts are on the bottom of the
socket for surface mounting with the motherboard.
The socket has the following solder ball material:
• Lead free SAC (SnAgCu) solder alloy with a silver (Ag) content between 3% and
4% and a melting temperature of approximately 217 °C. The alloy must be
Figure 2-4. Attachment to Motherboard

Thermal/Mechanical Design Guide 17
LGA1366 Socket
compatible with immersion silver (ImAg) motherboard surface finish and a SAC
alloy solder paste.
The co-planarity (profile) and true position requirements are defined in Appendix C.
2.3.3 Contacts
Base material for the contacts is high strength copper alloy.
For the area on socket contacts where processor lands will mate, there is a 0.381 m
[15 inches] minimum gold plating over 1.27 m [50 inches] minimum nickel
underplate.
No contamination by solder in the contact area is allowed during solder reflow.
2.3.4 Pick and Place Cover
The cover provides a planar surface for vacuum pick up used to place components in
the Surface Mount Technology (SMT) manufacturing line. The cover remains on the
socket during reflow to help prevent contamination during reflow. The cover can
withstand 260 °C for 40 seconds (typical reflow/rework profile) and the conditions
listed in the LGA1366 Socket Validation Reports without degrading.
As indicated in Figure 2-5, the cover remains on the socket during ILM installation, and
should remain on whenever possible to help prevent damage to the socket contacts.
Cover retention must be sufficient to support the socket weight during lifting,
translation, and placement (board manufacturing), and during board and system
shipping and handling.
The covers are designed to be interchangeable between socket suppliers. As indicated
in Figure 2-5, a Pin1 indicator on the cover provides a visual reference for proper
orientation with the socket.
See LGA1366_Socket_Pick_and_Place_Removal_Tool_rev2.0 for a drawing of a tool
designed to provide mechanical assistance during cover installation and removal.
Figure 2-5. Pick and Place Cover

LGA1366 Socket
18 Thermal/Mechanical Design Guide
2.4 Package Installation / Removal
As indicated in Figure 2-6, access is provided to facilitate manual installation and
removal of the package.
To assist in package orientation and alignment with the socket:
• The package Pin1 triangle and the socket Pin1 chamfer provide visual reference for
proper orientation.
• The package substrate has orientation notches along two opposing edges of the
package, offset from the centerline. The socket has two corresponding orientation
posts to physically prevent mis-orientation of the package. These orientation
features also provide initial rough alignment of package to socket.
• The socket has alignment walls at the four corners to provide final alignment of the
package.
See Appendix F for information regarding a tool designed to provide mechanical
assistance during processor installation and removal.
.
2.4.1 Socket Standoffs and Package Seating Plane
Standoffs on the bottom of the socket base establish the minimum socket height after
solder reflow and are specified in Appendix C.
Similarly, a seating plane on the topside of the socket establishes the minimum
package height. See Section 4.2 for the calculated IHS height above the motherboard.
Figure 2-6. Package Installation / Removal Features
alignment
walls
orientation
notch
orientation
post
access
Pin1 triangle
Pin1 chamfer
alignment
walls
orientation
notch
orientation
post
access
Pin1 triangle
Pin1 chamfer

Thermal/Mechanical Design Guide 19
LGA1366 Socket
2.5 Durability
The socket must withstand 30 cycles of processor insertion and removal. The max
chain contact resistance from Table 4-4 must be met when mated in the 1st and 30th
cycles.
The socket Pick and Place cover must withstand 15 cycles of insertion and removal.
2.6 Markings
There are three markings on the socket:
• LGA1366: Font type is Helvetica Bold - minimum 6 point (2.125 mm).
• Manufacturer's insignia (font size at supplier's discretion).
• Lot identification code (allows traceability of manufacturing date and location).
All markings must withstand 260°C for 40 seconds (typical reflow/rework profile)
without degrading, and must be visible after the socket is mounted on the
motherboard.
LGA1366 and the manufacturer's insignia are molded or laser marked on the side wall.
2.7 Component Insertion Forces
Any actuation must meet or exceed SEMI S8-95 Safety Guidelines for Ergonomics/
Human Factors Engineering of Semiconductor Manufacturing Equipment, example Table
R2-7 (Maximum Grip Forces). The socket must be designed so that it requires no force
to insert the package into the socket.
2.8 Socket Size
Socket information needed for motherboard design is given in Appendix C.
This information should be used in conjunction with the reference motherboard keep-
out drawings provided in Appendix B to ensure compatibility with the reference thermal
mechanical components.

LGA1366 Socket
20 Thermal/Mechanical Design Guide
2.9 LGA1366 Socket NCTF Solder Joints
Intel has defined selected solder joints of the socket as non-critical to function (NCTF)
for post environmental testing. The processor signals at NCTF locations are typically
redundant ground or non-critical reserved, so the loss of the solder joint continuity at
end of life conditions will not affect the overall product functionality. Figure 2-7
identifies the NCTF solder joints.
.
Note: For platforms supporting the DP processor land C3 is CTF.
§
Figure 2-7. LGA1366 NCTF Solder Joints
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B D F H K M P T V Y AB AD AF AH AK AM AP AT AV AY
A C E G J L N R U W AA AC AE AG AJ AL AN AR AU AW BA