AMD AMD Athlon 64 Guide

AMD Athlon™ 64 and
AMD Opteron™
ProcessorsThermal
Design Guide
Publication # 26633 Rev: 3.03
Issue Date: September 2003

© 2002—2003 Advanced Micro Devices, Inc. All rights reserved.
The contents of this document are provided in connection with Advanced
Micro Devices, Inc. (“AMD”) products. AMD makes no representations or
warranties with respect to the accuracy or completeness of the contents of this
publication and reserves the right to make changes to specifications and
product descriptions at any time without notice. No license, whether express,
implied, arising by estoppel, or otherwise, to any intellectual property rights
are granted by this publication. Except as set forth in AMD’s Standard Terms
and Conditions of Sale, AMD assumes no liability whatsoever, and disclaims
any express or implied warranty, relating to its products including, but not
limited to, the implied warranty of merchantability, fitness for a particular
purpose, or infringement of any intellectual property right.
AMD’s products are not designed, intended, authorized or warranted for use as
components in systems intended for surgical implant into the body, or in other
applications intended to support or sustain life, or in any other application in
which the failure of AMD’s product could create a situation where personal
injury, death, or severe property or environmental damage may occur. AMD
reserves the right to discontinue or make changes to its products at any time
without notice.
Trademarks
AMD, the AMD Arrow logo, AMD Athlon, AMD Opteron and combinations thereof, are trademarks of Advanced
Micro Devices, Inc.
Other product names used in this publication are for identification purposes only and may be trademarks of their
respective companies.

26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal
Design Guide
Contents
Revision History...............................................................................................................................9
Chapter 1 Introduction............................................................................................................11
1.1 Summary of Requirements ..............................................................................................11
Chapter 2 AMD Athlon™64 and AMD Opteron™ Processors Thermal
Requirements..........................................................................................................13
2.1 AMD Athlon™64, AMD Athlon 64 FX, and AMD Opteron™Processor
Specifications...................................................................................................................13
2.2 Socket Description...........................................................................................................14
2.3 Motherboard Component Height Restrictions.................................................................16
2.4 Thermal Solution Design Requirements..........................................................................18
2.5 Sample Heatsinks and Attachment Methods ...................................................................19
2.5.1 Thermal Reference Design Solution 1.........................................................................19
2.5.2 Thermal Reference Design Solution 2.........................................................................22
2.6 Thermal Solution Design Considerations ........................................................................25
2.6.1 Backplate Assembly.....................................................................................................25
2.6.2 Spring Clip...................................................................................................................25
2.6.3 Retention Frame...........................................................................................................26
2.6.4 Heatsink .......................................................................................................................26
2.6.5 Fans..............................................................................................................................30
2.6.6 Thermal Interface Material ..........................................................................................33
2.6.7 EMC Shield..................................................................................................................33
Chapter 3 Conclusion ..............................................................................................................35
AAppendix.................................................................................................................................37
A.1 Thermocouple Instrumentation........................................................................................37
A.1.1 Case Thermocouple Attachment..............................................................................37
A.1.2 Heatsink Thermocouple Attachment .......................................................................40
A.1.3 Ambient Thermocouple Attachment........................................................................40
A.2 Procedure for Clip Load Testing......................................................................................41
A.2.1 Equipment ................................................................................................................41
Contents 3

AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
A.2.2 Procedure................................................................................................................. 45
A.3 Motherboard Component Keep-Out Areas and Height Restriction Drawings................ 47
A.4 Thermal Reference Design Solution Component Drawings ........................................... 68
4 Contents

26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal
Design Guide
List of Figures
Figure 1. 754-pin µPGA Socket Used for the AMD Athlon™ 64 Processor..................................14
Figure 2. 940 pin µPGA Socket Used for the AMD Opteron™ Processor .....................................15
Figure 3. Motherboard Component Height Restrictions for the AMD Athlon 64 Processor
Thermal Solution ..............................................................................................................16
Figure 4. Motherboard Component Height Restrictions for the AMD Opteron Processor
Thermal Solution ..............................................................................................................17
Figure 5. AMD Athlon 64 and AMD Opteron Processors Thermal Reference Design
Solution 1 .........................................................................................................................20
Figure 6. Thermal Reference Design Solution 1 Components Assembled for Shipment ...............21
Figure 7. View of an Installed Heatsink Utilizing the Thermal Reference Design
Solution 1 .........................................................................................................................21
Figure 8. Exploded View of the Components Utilized in the AMD Athlon 64 and
AMD Opteron Processors Thermal Reference Design Solution 2..................................23
Figure 9. Thermal Reference Design Solution 2 Components Configured for Shipment ...............24
Figure 10. View of a Heatsink Installation Utilizing the Thermal Reference Design
Solution 2 ......................................................................................................................24
Figure 11. Example of a Low-Cost Heatsink Using Aluminum Extrusion Technology.................27
Figure 12. High Performance Heatsink with Copper Slug Embedded in the Base .........................28
Figure 13. Required Exhaust Airflow Direction for Motherboard Voltage Regulator
Cooling...........................................................................................................................29
Figure 14. Typical Temperature-Fan Speed Relation for Speed-Controlled Fan............................31
Figure 15. Acoustic Noise from Sample Thermal Solutions with a 70x15 mm Fan.......................32
Figure 16. Diagonals Marked on Processor to Locate Center .........................................................37
Figure 17. Thermocouple Taped to Processor Lid...........................................................................38
Figure 18. Thermocouple Attached to Processor with Strain Relief on Package and PCB.............39
Figure 19. Heatsink with Thermocouple Relief Groove Machined into Base.................................39
Figure 20. Heatsink Thermocouple Relief Groove and Measurement Hole ...................................40
Figure 21. An Entran ELW-D1 Load Cell.......................................................................................41
Figure 22. Load Cell Inserted into the Load Cell Fixture................................................................42
Figure 23. Drawing of Load Cell Fixture for the Entran ELW-D1 Load Cell ................................43
Figure 24. Test Board with a Load Cell Fixture Installed in the Socket 754 ..................................45
Figure 25. Heatsink Installation over the Load Cell Fixture ...........................................................46
List of Figures 5

AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
6 List of Figures

26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal
Design Guide
List of Tables
Table 1. Mechanical and Thermal Specifications for the AMD Athlon™ 64 and AMD Opteron™
Processors .........................................................................................................................13
Table 2. Thermal Solution Design Requirements for the AMD Athlon 64 and AMD Opteron
Processors .........................................................................................................................18
Table 3. Components for the AMD Athlon 64 and AMD Opteron Processors Thermal Reference
Design Solution 1..............................................................................................................19
Table 4. Components for the AMD Athlon 64 and AMD Opteron Processors Thermal Reference
Design Solution 2..............................................................................................................22
Table 5. Chemical Composition of SK7 Spring Steel .....................................................................26
Table 6. Suggested Thermal Interface Materials .............................................................................33
List of Tables 7

AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
8 List of Tables

Preliminary Information
26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
Revision History
Date Rev Description
September 2003 3.03 Revision 3.03 includes the addition of information for the
AMD Opteron™ processor and the following changes:
• In Chapter 2, added AMD Athlon™ 64 FX processor
information in Section 2.1 on page 13, revised Table 1 on page
13, added Figure 2 on page 15, revised Figure 3 on page 16,
added Figure 4 on page 17, revised Table 2 on page 18,
revised Table 3 on page 19, revised Table 4 on page 22,
revised Section 2.6 on page 25, added Section 2.6.4.3,
“Required Exhaust Airflow Direction,” on page 29, added
Figure 13 on page 29, revised Section 2.6.5 on page 30, added
Figure 14 on page 31, added Figure 15 on page 32, and revised
Table 6 on page 33.
• In the Appendix , revised Socket 754 diagrams and added
Socket 940 diagrams to Section A.3 on page 47. Revised
diagrams in Section A.4 on page 68.
February 2003 3.02 Revised Figure 3, “Motherboard Component Height Restrictions for
the AMD Athlon™ 64 Processor Thermal Solution,” on page 16, and
the drawings in the Appendix, section A3, “Motherboard Component
Keep-Out Areas and Height Restriction Drawings,” on pages 35–44.
November 2002 3.01 Title changed to “AMD Athlon™ 64 Processor Thermal Design
Guide.”
October 2002 3.00 Public release
9Revision History

AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
10

Preliminary Information
26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
Chapter 1 Introduction
This document specifies performance requirements for the design of thermal and mechanical
solutions for the AMD Athlon™ 64 and AMD Opteron™ processors, utilizing AMD64
architecture. Detailed drawings, descriptions, and design targets are provided to help
manufacturers, suppliers, and engineers meet requirements for the AMD Athlon 64 and
AMD Opteron processors.
1.1 Summary of Requirements
To allow optimal reliability of the AMD Opteron and AMD Athlon 64 processor-based systems,
the thermal and cooling solution should dissipate heat from a processor operating at its maximum
thermal power. The sections in this document specify required values for the thermal and
mechanical parameters. This document provides two methods of creating a solution that satisfy the
thermal and mechanical requirements for these processors. By setting a high-power target for the
initial design, the thermal-design engineer may avoid redesign of the processor cooling solution
for subsequent processors.
Chapter 1 Introduction 11

Preliminary Information
AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
12 Introduction Chapter 1

Preliminary Information
26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
Chapter 2 AMD Athlon™64 and AMD Opteron™
Processors Thermal Requirements
This chapter describes thermal solutions for the AMD Athlon™ 64, AMD Athlon 64 FX, and
AMD Opteron™ processors.
2.1 AMD Athlon™64, AMD Athlon 64 FX, and
AMD Opteron™Processor Specifications
The objective of thermal solutions, commonly referred to as heatsinks, is to maintain the processor
temperature within specified limits. The main factors that must be considered during the design of
a thermal solution are the thermal performance, physical mounting, acoustic noise, mass,
reliability, and cost.
This document presents the thermal and mechanical specifications, and heatsink requirements for
the AMD Athlon 64, AMD Athlon 64 FX, and AMD Opteron processors. The thermal and
mechanical specifications for the 940-pin AMD Athlon 64 FX processor are the same as those for
the AMD Opteron processor. For the thermal and mechanical requirements for the
AMD Athlon 64 FX processor, refer to the AMD Opteron processor information presented in this
document.
Table 1 lists the pertinent AMD Athlon 64 and AMD Opteron processor specifications for a
thermal solution design.
Table 1. Mechanical and Thermal Specifications for the AMD Athlon™ 64 and
AMD Opteron™ Processors
Symbol Description Maximum Value Notes
TCASE Maximum case
temperature
62–70°C Case temperature will be
defined in the processor
datasheet
ACPU Processor contact area 1400 sq. mm Interfaces with heatsink
Form factor Processor form factor µPGA PGA Socket 754 form factor
for AMD Athlon™ 64
processor
Form factor Processor form factor µPGA PGA Socket 940 form factor
for AMD Opteron™ processor
Chapter 2 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements 13

Preliminary Information
AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
2.2 Socket Description
Figure 1 shows a three-dimensional view of the Socket 754, which is a socket based on surface
mount technology. The pin array is 29x29 on a 1.27 mm pitch with a 9x9 depopulation in the
center. In addition, three pins are removed from the A1 corner of the package, and a single pin is
removed from the other three corners. The electrical and mechanical connection to the
motherboard is made with a small solder ball at each socket contact. This type of connection does
not allow for a large mass, like a heatsink, to be attached to the socket. Therefore, independent
support structures are required for mounting the heatsink.
Figure 1. 754-pin µPGA Socket Used for the AMD Athlon™ 64 Processor
14 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements Chapter 2

Preliminary Information
26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
Figure 2 shows a three-dimensional view of the Socket 940, which is used for the AMD Opteron
processor. As with the Socket 754, it has a 1.27 mm array pitch but has a 31x31 pin array with
various pins removed from the package for keying and mechanical support.
Figure 2. 940-pin µPGA Socket Used for the AMD Opteron™ Processor
Chapter 2 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements 15

Preliminary Information
AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
2.3 Motherboard Component Height Restrictions
The mounting solution for the heatsink requires attachment to the motherboard. As such, this
solution calls for a standard motherboard keepout region and mounting holes for the processor. An
overview of the motherboard component restrictions for the AMD Athlon 64 is shown in Figure 3.
A complete detailed set of drawings is shown in Appendix A.3 on page 47. Thermal-solution
designers must adhere to these geometric restrictions to be compatible with the motherboards
designed for the AMD Athlon 64 processor. Similarly, overview of the motherboard component
restrictions for the AMD Opteron is shown in Figure 4 on page 17.
Figure 3. Motherboard Component Height Restrictions for the AMD Athlon™ 64 Processor
Thermal Solution
16 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements Chapter 2

Preliminary Information
26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
Figure 4. Motherboard Component Height Restrictions for the AMD Opteron™ Processor
Thermal Solution
Chapter 2 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements 17

Preliminary Information
AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
2.4 Thermal Solution Design Requirements
To maintain the case temperature of the processor below the maximum specification, certain
heatsink design parameters must be considered. Table 2 provides the design-target specifications
that must be met for the AMD Athlon 64 and AMD Opteron processors to operate reliably.
Table 2. Thermal Solution Design Requirements for the AMD Athlon™ 64 and
AMD Opteron™ Processors
Symbol Description Minimum Maximum Notes
L Length of heatsink 77 mm 77 mm Measurements are for
the entire assembly,
including attached fan.
W Width of heatsink 68 mm 68 mm
H Height of heatsink 60 mm
θCA Case-to-ambient
thermal resistance
0.28°C/W
mHS Mass of heatsink 450 g
FCLIP Clip force 60 lb 90 lb
TALocal ambient
temperature near
processor
42°C
32 dbA The preferred level is to
have no annoying tones.
LPA Sound pressure
measured 1 m
from fan 38 dbA Maximum level is at
room temperature with
no annoying tones
18 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements Chapter 2

Preliminary Information
26633 Rev. 3.03 September 2003 AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
2.5 Sample Heatsinks and Attachment Methods
The following sections provide two possible thermal design solutions and the specifics on their
attachment to the motherboard.
2.5.1 Thermal Reference Design Solution 1
Table 3 lists the parts that comprise the thermal reference design solution 1 for the
AMD Opteron and AMD Athlon 64 processors. The heatsink installers do not have to assemble
each individual component. The heatsink suppliers package the parts with some of the components
already assembled. The logical breakdown consists of the components that reside on the topside of
the motherboard, the heatsink, and the components that reside on the bottom side of the
motherboard, the backplate.An exploded view showing the components used in the thermal
reference design solution 1 is shown in Figure 5 on page 20.
Due to the high load required to attach the heatsink to the processor, a backplate is used on the
backside of the motherboard to minimize possible warping of the motherboard due to clip forces
on the heatsink. Figure 6 on page 21 shows the assembly components grouped for shipment and
how they are used during the final assembly of the system.
When developing the thermal reference design solution 1, AMD took into consideration the
manufacturing and assembly ease of the solution. The thermal reference design solution 1 requires
a screwdriver to install the heatsink. The mechanical advantage of the screw is that it applies a
large force to the clip. Minimizing installation fatigue was a significant factor in selecting the use
of screws in this thermal solution. During installation each screw is driven until it bottoms out on
the retention frame. This may require a torque of 6 to 12 in-lbs. Figure 7 on page 21 shows a
heatsink installed according to the thermal reference design solution 1.
Table 3. Components for the AMD Athlon™ 64 and AMD Opteron™ Processors Thermal
Reference Design Solution 1
Part Description Material Quantity
Heatsink Aluminum 1
Fan Plastic 1
Mounting frame Lexan, 20% glass filled 1
Spring clip SK7 heat treated spring steel 1
6-32x1” pan head screw Stainless steel 2
Backplate Low carbon steel, anti-corrosive finish 1
Insulator Formex GK-17 1
EMC shield Stainless steel 1
Chapter 2 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements 19

Preliminary Information
AMD Athlon™ 64 and AMD Opteron™ Processors
Thermal Design Guide
26633 Rev. 3.03 September 2003
Figure 5. AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Reference Design
Solution 1
20 AMD Athlon™ 64 and AMD Opteron™ Processors Thermal Requirements Chapter 2