Intel E6700 Mechanical Design Guidelines - Page 40

Balanced Technology Extended (BTX) Thermal/Mechanical Design Information

40

Thermal and Mechanical Design Guidelines

5.1.2

Acoustics

To optimize acoustic emission by the fan heatsink assembly, the Type II reference

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

performance at higher fan inlet temperatures (T

A

) and the appropriate thermal

performance with improved acoustics at lower fan inlet temperatures. Using the

example in Table 5–2 for the Intel Core™2 Duo processor with 4 MB cache at T

C-MAX

of

60.1 °C the required fan speed necessary to meet thermal specifications can be

controlled by the fan inlet temperature and should comply with requirements in

Table 5–2.

Table 5–2. Acoustic Targets

Fan Speed

RPM

Thermistor

Set Point

Acoustic

Thermal

Requirements,

Ψ

ca

Notes

~ 5300

High

T

A

≥ 35

°C

≤

6.4 BA

0.38

°

C/W

Case 1:

Thermal Design Power

Maximum fan speed

100% PWM duty cycle

~ 2500

Low

T

A

= 23 °C

No Target

Defined

0.56

°

C/W

Case 2

Thermal Design Power

System (PSU, HDD, TMA)

Fan speed limited by the fan

hub thermistor

~ 1400

Low

T

A

= 23 °C

≤

3.4 BA

~0.87

°

C/W

Case 3

50% Thermal Design Power

TMA Only

~ 1400

Low

T

A

= 23 °C

≤

4.0 BA

~0.87

°

C/W

Case 3

50% Thermal Design Power

System (PSU, HDD, TMA)

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.

2.

Acoustic testing will be for the TMA only when installed in a BTX S2 chassis for Case 1

and 3.

3.

Acoustics testing for Case 2 will be system level in the same a BTX S2 reference chassis

and commercially available power supply. Acoustic data for Case 2 will be provided in

the validation report but this condition is not a target for the design. The acoustic

model is predicting that the power supply fan will be the acoustic limiter.

4.

The fan speeds (RPM) are estimates for one of the two reference fans and will be

adjusted to meet thermal performance targets then acoustic target during validation.

The designer should identify the fan speed required to meet the effective fan curve

shown in Section 5.1.3.

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’s recommendation is to use the

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

digital thermal sensor. 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.

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 40

Acoustics - core speeds

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