Order Number: 323107-002US
Intel
®
Xeon
®
Processor
C5500/C3500 Series and LGA1366
Socket
Thermal/Mechanical Design Guide
August 2010
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
Thermal/Mechanical Design Guide August 2010
2 Order Number: 323107-002US
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

2.1.7 Processor Materials 16
2.1.8 Processor Markings 16
2.1.9 Processor Land Coordinates 17
3 LGA1366 Socket 18
3.1 Board Layout 20
3.2 Attachment to Motherboard 21
3.3 Socket Components 21
3.3.1 Socket Body Housing 21
3.3.2 Solder Balls 21
3.3.3 Contacts 22
3.3.4 Pick and Place Cover 22
3.4 Package Installation / Removal 23
3.4.1 Socket Standoffs and Package Seating Plane 23
3.5 Durability 24
3.6 Markings 24
3.7 Component Insertion Forces 24
3.8 Socket Size 24
3.9 LGA1366 Socket NCTF Solder Joints 24
4 Independent Loading Mechanism (ILM) 26
4.1 Design Concept 26
4.1.1 ILM Cover Assembly Design Overview 26
4.1.2 ILM Back Plate Design Overview 27
4.2 Assembly of ILM to a Motherboard 28
5 LGA1366 Socket and ILM Electrical, Mechanical and Environmental Specifications 31
5.1 Component Mass 31
5.2 Package/Socket Stackup Height 31
5.3 Socket Maximum Temperature 31
5.4 Loading Specifications 33
5.4.1 Board Deflection Guidance 33
5.5 Electrical Requirements 34

7.6.1 Fan Speed Control 61
7.6.2 PECI Averaging and Catastrophic Thermal Management 62
7.6.3 Intel
®
Turbo Boost Technology 62
7.6.4 Absolute Processor Temperature 63
7.6.5 Custom Heat Sinks For UP ATCA 63
8 Quality and Reliability Requirements 66
8.1 Use Conditions 66
8.2 Intel Reference Component Validation 67
8.2.1 Board Functional Test Sequence 67
8.2.2 Post-Test Pass Criteria 68
8.2.3 Recommended BIOS/Processor/Memory Test Procedures 68
8.3 Material and Recycling Requirements 68
A Component Suppliers 70
B Mechanical Drawings 72
C Socket Mechanical Drawings 89
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
August 2010 Thermal/Mechanical Design Guide
Order Number: 323107-002US 5

Figures
1-1 Intel
®
Xeon
®

®
Xeon
®
Processor LC5528 Thermal Profile 40
6-4 Intel
®
Xeon
®
Processor LC5518 Thermal Profile 42
6-5 Intel
®
Celeron® Processor P1053 Thermal Profile 43
6-6 Intel
®
Xeon
®
Processor LC3528 Thermal Profile 44
6-7 Intel
®
Xeon
®
Processor LC3518 Thermal Profile 46
6-8 TTV Case Temperature (TCASE) Measurement Location 47
6-9 Frequency and Voltage Ordering 49
7-1 1U Heatsink Performance Curves 55
7-2 ATCA Heatsink Performance Curves 56
7-3 TTV Die Size and Orientation 57
7-4 1U Reference Heatsink Assembly 57
7-5 Processor Thermal Characterization Parameter Relationships 59
7-6 NEBS Thermal Profile 60

Tables
1-1 Reference Documents 9
1-2 Terms and Descriptions 9
2-1 Processor Loading Specifications 15
2-2 Package Handling Guidelines 15
2-3 Processor Materials 16
5-1 Socket Component Mass 31
5-2 1366-land Package and LGA1366 Socket Stackup Height 31
5-3 Socket and ILM Mechanical Specifications 33
5-4 Electrical Requirements for LGA1366 Socket 34
6-1 Intel
®
Xeon
®
Processor EC5549 and EC5509 Thermal Specifications 37
6-2 Intel
®
Xeon
®
Processor EC5549 and EC5509 Thermal Profile 38
6-3 Intel
®
Xeon
®
Processor EC3539 and EC5539 Thermal Specifications 38
6-4 Intel
®
Xeon
®
Processor EC3539 and EC5539 Thermal Profile 39

6-11 Intel
®
Xeon
®
Processor LC3528 Thermal Specifications 44
6-12 Intel
®
Xeon
®
Processor LC3528 Thermal Profile 45
6-13 Intel
®
Xeon
®
Processor LC3518 Thermal Specifications 45
6-14 Intel
®
Xeon
®
Processor LC3518 Thermal Profile 46
6-15 GetTemp0() Error Codes 53
7-1 Boundary Conditions and Performance Targets 54
7-2 Fan Speed Control, TCONTROL and DTS Relationship 61
7-3 TCONTROL Guidance 62
8-1 Server Use Conditions Environment (System Level) 66
8-2 Server Use Conditions Environment (System Level) 67
A-1 Heatsinks and Thermal Interface Material 70
A-2 LGA1366 Socket and ILM Components 71
B-1 Mechanical Drawing List 72
C-1 Mechanical Drawing List 89

• The LGA1366 socket and the Independent Loading Mechanism (ILM) and back
plate.
The goals of this document are:
• To assist board and system thermal mechanical designers.
• To assist designers and suppliers of processor heatsinks.
Other processor specifications are provided in the Intel
®
Xeon
®
Processor C5500/
C3500 Series Datasheet.
Figure 1-1. Intel
®
Xeon
®
Processor C5500/C3500 Series Socket Stack-up
Heatsink
Socket and ILM
Back Plate
Introduction
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
Thermal/Mechanical Design Guide August 2010
9 Order Number: 323107-002US
1.1 Reference Documents
Material and concepts in the following documents may be beneficial when reading this
document.

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.
IMON The current monitor input to the CPU. The VRM tells the CPU how much current it is
drawing.
LGA1366 socket The processor mates with the system board through this surface mount, 1366-land
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.
Ψ
CA
Case-to-ambient thermal characterization parameter (psi). A measure of thermal
solution performance using total package power. Defined as (T
CASE
– T
LA
) / Total
Package Power. Heat source should always be specified for Ψ measurements.
Ψ
CS
Case-to-sink thermal characterization parameter. A measure of thermal interface
material performance using total package power. Defined as (T

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.
T
CONTROL
T
control
is a static value below TCC activation used as a trigger point for fan speed
control.
TDP Thermal Design Power: Thermal solution must 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.
T
LA
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.
T
SA
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.

IHS
Substrate

LGA1366 Socket
System Board

CapacitorsTIM
IHS
Substrate

LGA

System Board

Capacitors

Die
TIM
Package Mechanical Specifications
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
Thermal/Mechanical Design Guide August 2010
12 Order Number: 323107-002US
2.1.1 Package Mechanical Drawing

G
F
E
D
C
B
A
A
A
R
D
E
C
C
4X RM
1
M
2
M
3
F
4
F
2
B
1
C
1
C
3

2200 MISSION COLLEGE BLVD.
P.O. BOX 58119
SANTA CLARA, CA 95052-8119
TITLE
EMTS DRAWING
SIZE DRAWING NUMBER REV
A1 D76126 7
SCALE: 2:1
DO NOT SCALE DRAWING
SHEET 1 OF 2
FINISHMATERIAL
DATEAPPROVED BY
DATECHECKED BY
DATEDRAWN BY
DATEDESIGNED BY
UNLESS OTHERWISE SPECIFIED
INTERPRET DIMENSIONS AND TOLERANCES
IN ACCORDANCE WITH ASME Y14.5M-1994
DIMENSIONS ARE IN MILLIMETERS
ALL UNTOLERANCED LINEAR
DIMENSIONS ±0
ANGLES ± 0.5
THIRD ANGLE PROJECTION
SEE DETAIL B
SEE DETAIL B
SEE DETAIL B
SEE DETAIL B
IHS LID
SEE DETAIL B
PIN 1

N
M
L
K
J
H
G
F
E
D
C
B
A
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
SEE DETAIL A
SECTION A-A
DETAIL A
SCALE 20:1
PACKAGE SUBSTRATE IHS SEALANT
IHS LID
DETAIL
C
SCALE 20:1
DETAIL B
SUBSTRATE ALIGNMENT FIDUCIAL
X5
SCALE 35:1
SYMBOL
MILLIMETERS

42.672 BASIC
G
2
40.64 BASIC
H
1
21.336 BASIC
H
2
20.32 BASIC
J
1
1.016 BASIC
J
2
1.016 BASIC
M
1
0.19 0.23
M
2
0.88 0.96
M
3
0.53 0.61
0.203
0.08
0.203 C
0.203 C D E
0.071 C

H
H
H
C
9.455
7.2
1.06 MAX
COMPONENT HEIGHT
T
1
T
2
V
1
V
2
2X 36.5
2X 39
14.4
18.91
E
G
E
G

THIS DRAWING CONTAINS INTEL CORPORATION CONFIDENTIAL INFORMATION. IT IS DISCLOSED IN CONFIDENCE AND ITS CONTENTS
MAY NOT BE DISCLOSED, REPRODUCED, DISPLAYED OR MODIFIED, WITHOUT THE PRIOR WRITTEN CONSENT OF INTEL CORPORATION.

THIS DRAWING CONTAINS INTEL CORPORATION CONFIDENTIAL INFORMATION. IT IS DISCLOSED IN CONFIDENCE AND ITS CONTENTS
MAY NOT BE DISCLOSED, REPRODUCED, DISPLAYED OR MODIFIED, WITHOUT THE PRIOR WRITTEN CONSENT OF INTEL CORPORATION.

AF
AE
AD
AC
AB
AA
Y
W
V
U
T
R
P
N
M
L
K
J
H
G
F
E
D
C
B
A
DETAIL D
SCALE 15:1
0.23 C H E
M N

V
1
0.2
V
2
11.7
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
August 2010 Thermal/Mechanical Design Guide
Order Number: 323107-002US 15

Package Mechanical Specifications
2.1.2 Processor Component Keep-Out Zones
The processor may contain components on the substrate that define component
keep-out zone requirements. A thermal and mechanical solution design must not
intrude into the required keep-out zones. Do not contact the Test Pad Area with
conductive material. Decoupling capacitors are typically mounted to either the topside
or land-side of the package substrate. See Figure 2-2 and Figure 2-3 for keep-out
zones. The location and quantity of package capacitors may change due to
manufacturing efficiencies but will remain within the component keep-in.
2.1.3 Package Loading Specifications
Table 2-1 provides load specifications for the processor package. These maximum
limits should not be exceeded during heatsink assembly, shipping conditions, or
standard use condition. Exceeding these limits during test may result in component
failure. The processor substrate should not be used as a mechanical reference or load-
bearing surface for thermal solutions.
.

®
Processor C5500/C3500 Series and LGA1366 Socket
Thermal/Mechanical Design Guide August 2010
16 Order Number: 323107-002US
2.1.6 Processor Mass Specification
The typical mass of the processor is 35 grams. This mass [weight] includes all the
components that are included in the package.
2.1.7 Processor Materials
Table 2-3 lists some of the package components and associated materials.

2.1.8 Processor Markings
Figure 2-4 shows the topside markings on the processor. This diagram is to aid in the
identification of the processor.
Table 2-3. Processor Materials
Component Material
Integrated Heat Spreader (IHS) Nickel Plated Copper
Substrate Fiber Reinforced Resin
Substrate Lands Gold Plated Copper
Figure 2-4. Processor Top-Side Markings
GRP1LINE1
GRP1LINE2
G2L1
G2L2
G3L1
G3L2
Legend: Mark Text (Engineering Mark):
GRP1LINE1: INTEL{M}{C}’YY
GRP1LINE2: INTEL CONFIDENTIAL
GRP1LINE3: QDF ES XXXXX
GRP1LINE4: FORECAST-NAME

LGA1366 Socket
3 LGA1366 Socket
This section describes a surface mount, LGA (Land Grid Array) socket intended for the
Intel
®
Xeon
®
processor C5500/C3500 series in the Picket Post 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 43 x 41
grid array with 21 x 17 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
Section 5.
Figure 3-1. LGA1366 Socket with Pick and Place Cover Removed
socket
cavity
package socket
cavity
package
LGA1366 Socket
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket

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

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

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
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.
Figure 3-4. Attachment to Motherboard
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
August 2010 Thermal/Mechanical Design Guide
Order Number: 323107-002US 22

LGA1366 Socket
3.3.3 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 μm
[15 μinches] minimum gold plating over 1.27 μm [50 μinches] minimum nickel
underplate.
No contamination by solder in the contact area is allowed during solder reflow.
3.3.4 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 Section 6 without degrading.

3.4.1 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 5.2 for the calculated IHS height above the motherboard.
Figure 3-6. 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
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
August 2010 Thermal/Mechanical Design Guide

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 3-7 identifies the NCTF solder joints.
LGA1366 Socket
Intel
®
Xeon
®
Processor C5500/C3500 Series and LGA1366 Socket
Thermal/Mechanical Design Guide August 2010
25 Order Number: 323107-002US
.
Note: For platforms supporting the DP processor land C3 is CTF.
§
Figure 3-7. LGA1366 NCTF Solder Joints
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 BB
1
3
7
5
9
11
15
13
17
19
23
21
25

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