Intel E6700 Mechanical Design Guidelines - Page 54

ATX Thermal/Mechanical Design Information

54

Thermal and Mechanical Design Guidelines

6.2.2

Acoustics

To optimize acoustic emission by the fan heatsink assembly, the reference design

implements a variable speed fan. A variable speed fan allows higher thermal

performance at higher fan inlet temperatures (T

A

) and lower thermal performance with

improved acoustics at lower fan inlet temperatures. The required fan speed necessary

to meet thermal specifications can be controlled by the fan inlet temperature and

should comply with requirements in Table 6–2.

Table 6–2. Acoustic Results for ATX Reference Heatsink (E18764-001)

Fan

Speed

RPM

Thermist

or Set

Point

Acoustic

Thermal Requirements,

Ψ

ca

Notes

3900

High

T

A

= 40 °C

5.0 BA

•

0.50

°

C/W (Core™2 Duo processor E8000 series 6

MB)

•

0.52

°


MB, Pentium dual-core processor E6000, E5000

series 2 MB, and Intel

®

Celeron

®

processor E3000

series with 1 MB)

2000

Low

T

A

= 30 °C

3.5 BA

•

0.65

°

C/W (Core™2 Duo processor E8000 series

with 6 MB)

•

0.68

°


MB, Pentium dual-core processor E6000, E5000

series 2 MB, and Intel

®

Celeron

®

processor E3000

series with 1 MB)

Thermal Design

Power, Fan

speed limited

by the fan hub

thermistor

NOTES:

1.

Acoustic performance is defined in terms of measured sound power (LwA) as defined in

ISO 9296 standard, and measured according to ISO 7779.

While the fan hub thermistor helps optimize acoustics at high processor workloads by

adapting the maximum fan speed to support the processor thermal profile, additional

acoustic improvements can be achieved at lower processor workload by using the

T

CONTROL

specifications described in Section 2.2.4. Intel recommendation is to use the

fan with 4 Wire PWM Controlled to implement fan speed control capability based

digital thermal sensor temperature. Refer to Chapter 7 for further details.

Note:

Appendix F gives detailed fan performance for the Intel reference thermal solutions

with 4 Wire PWM Controlled fan.

6.2.3

Altitude

Many companies design products that must function reliably at high altitude, typically

1,500 m [5,000 ft] or more. Air-cooled temperature calculations and measurements at

the test site elevation must be adjusted to take into account altitude effects like

variation in air density and overall heat capacity. This often leads to some degradation

in thermal solution performance compared to what is obtained at sea level, with lower

fan performance and higher surface temperatures. The system designer needs to

account for altitude effects in the overall system thermal design to make sure that the

T

C

requirement for the processor is met at the targeted altitude.

Section	Page
1 Introduction	9
1.1 Document Goals and Scope	9
1.1.1 Importance of Thermal Management	9
1.1.2 Document Goals	9
1.1.3 Document Scope	10
1.2 References	11
1.3 Definition of Terms	11
2 Processor Thermal/Mechanical Information	13
2.1 Mechanical Requirements	13
2.1.1 Processor Package	13
2.1.2 Heatsink Attach	15
2.1.2.1 General Guidelines	15
2.1.2.2 Heatsink Clip Load Requirement	15
2.1.2.3 Additional Guidelines	16
2.2 Thermal Requirements	16
2.2.1 Processor Case Temperature	16
2.2.2 Thermal Profile	17
2.2.3 Thermal Solution Design Requirements	17
2.2.4 TCONTROL	18
2.3 Heatsink Design Considerations	19
2.3.1 Heatsink Size	20
2.3.2 Heatsink Mass	20
2.3.3 Package IHS Flatness	21
2.3.4 Thermal Interface Material	21
2.4 System Thermal Solution Considerations	22
2.4.1 Chassis Thermal Design Capabilities	22
2.4.2 Improving Chassis Thermal Performance	22
2.4.3 Summary	23
2.5 System Integration Considerations	23
3 Thermal Metrology	25
3.1 Characterizing Cooling Performance Requirements	25
3.1.1 Example	26
3.2 Processor Thermal Solution Performance Assessment	27
3.3 Local Ambient Temperature Measurement Guidelines	27
3.4 Processor Case Temperature Measurement Guidelines	30
4 Thermal Management Logic and Thermal Monitor Feature	31
4.1 Processor Power Dissipation	31
4.2 Thermal Monitor Implementation	31
4.2.1 PROCHOT# Signal	32
4.2.2 Thermal Control Circuit	32
4.2.2.1 Thermal Monitor	32
4.2.3 Thermal Monitor 2	33
4.2.4 Operation and Configuration	34
4.2.5 On-Demand Mode	35
4.2.6 System Considerations	35
4.2.7 Operating System and Application Software Considerations	36
4.2.8 THERMTRIP# Signal	36
4.2.9 Cooling System Failure Warning	36
4.2.10 Digital Thermal Sensor	37
4.2.11 Platform Environmental Control Interface (PECI)	38
5 Balanced Technology Extended (BTX) Thermal/Mechanical Design Information	39
5.1 Overview of the BTX Reference Design	39
5.1.1 Target Heatsink Performance	39
5.1.2 Acoustics	40
5.1.3 Effective Fan Curve	41
5.1.4 Voltage Regulator Thermal Management	42
5.1.5 Altitude	43
5.1.6 Reference Heatsink Thermal Validation	43
5.2 Environmental Reliability Testing	43
5.2.1 Structural Reliability Testing	43
5.2.1.1 Random Vibration Test Procedure	43
5.2.1.2 Shock Test Procedure	44
5.2.2 Power Cycling	45
5.2.3 Recommended BIOS/CPU/Memory Test Procedures	46
5.3 Material and Recycling Requirements	46
5.4 Safety Requirements	47
5.5 Geometric Envelope for Intel® Reference BTX Thermal Module Assembly	47
5.6 Preload and TMA Stiffness	48
5.6.1 Structural Design Strategy	48
5.6.2 TMA Preload verse Stiffness	48
6 ATX Thermal/Mechanical Design Information	51
6.1 ATX Reference Design Requirements	51
6.2 Validation Results for Reference Design	53
6.2.1 Heatsink Performance	53
6.2.2 Acoustics	54
6.2.3 Altitude	54
6.2.4 Heatsink Thermal Validation	55
6.3 Environmental Reliability Testing	55
6.3.1 Structural Reliability Testing	55
6.3.1.1 Random Vibration Test Procedure	55
6.3.1.2 Shock Test Procedure	56
6.3.2 Power Cycling	57
6.3.3 Recommended BIOS/CPU/Memory Test Procedures	58
6.4 Material and Recycling Requirements	58
6.5 Safety Requirements	59
6.6 Geometric Envelope for Intel® Reference ATX Thermal Mechanical Design	59
6.7 Reference Attach Mechanism	60
6.7.1 Structural Design Strategy	60
6.7.2 Mechanical Interface to the Reference Attach Mechanism	61
7 Intel® Quiet System Technology (Intel® QST)	63
7.1 Intel® QST Algorithm	63
7.1.1 Output Weighting Matrix	64
7.1.2 Proportional-Integral-Derivative (PID)	64
7.2 Board and System Implementation of Intel® QST	66
7.3 Intel® QST Configuration and Tuning	68

Intel E6700 Mechanical Design Guidelines - Page 54

Acoustics, Altitude

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