Intel QX9770 Design Guidelines - Page 12

LGA775 Socket Heatsink Loading

12

Thermal and Mechanical Design Guidelines

Term

Description

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.

P

MAX

The maximum power dissipated by a semiconductor component.

TDP

Thermal Design Power: a power dissipation target based on worst-case applications.

Thermal solutions should be designed to dissipate the thermal design power.

IHS

Integrated Heat Spreader: a thermally conductive lid integrated into a processor

package to improve heat transfer to a thermal solution through heat spreading.

LGA775 Socket

The surface mount socket designed to accept the processors in the 775–Land LGA

package.

ACPI

Advanced Configuration and Power Interface.

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.

Thermal

Monitor

A feature on the processor that attempts to keep the processor die temperature within

factory specifications.

TCC

Thermal Control Circuit: Thermal Monitor uses the TCC to reduce die temperature by

lowering effective processor frequency when the die temperature has exceeded its

operating limits.

DTS

Digital Thermal Sensor: Processor die sensor temperature defined as an offset from

the onset of PROCHOT#.

T

DIODE

Temperature reported from the on-die thermal diode.

FSC

Fan Speed Control:

Thermal solution that includes a variable fan speed which is

driven by a PWM signal and uses the digital thermal sensor as a reference to change

the duty cycle of the PWM signal.

T

CONTROL_BASE

Constant from the processor datasheet that is added to the

T

CONTROL_OFFSET

that

results in the value for

T

CONTROL

T

CONTROL_OFFSET

Value read by the BIOS from a processor MSR and added to the

T

CONTROL_BASE

that

results in the value for

T

CONTROL

T

CONTROL

T

CONTROL

is the specification limit for use with the digital thermal sensor.

PWM

Pulse width modulation is a method of controlling a variable speed fan.

The enabled

4 wire fans use the PWM duty cycle % from the fan speed controller to modulate the

fan speed.

Health Monitor

Component

Any standalone or integrated component that is capable of reading the processor

temperature and providing the PWM signal to the 4 pin fan header.

BTX

Balanced Technology Extended

TMA

Thermal Module Assembly.

The heatsink, fan and duct assembly for the BTX thermal

solution

§

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 The Pump Assembly 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 TCONTROL	18
2.3 Heatsink Design Considerations	19
2.3.1 Heatsink Size	20
2.3.2 Package IHS Flatness	20
2.3.3 Thermal Interface Material	21
2.4 System Thermal Solution Considerations	21
2.4.1 Chassis Thermal Design Capabilities	21
2.4.2 Improving Chassis Thermal Performance	21
2.4.3 Summary	22
2.5 System Integration Considerations	22
3 Thermal Metrology	23
3.1 Characterizing Cooling Performance Requirements	23
3.1.1 Example	25
3.2 Processor Thermal Solution Performance Assessment	26
3.3 Local Ambient Temperature Measurement Guidelines	26
3.4 Processor Case Temperature Measurement Guidelines	29
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
4.2.3 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 Intel Thermal/Mechanical Reference Design Information	39
5.1 Validation Results for the ATX Reference Design	39
5.1.1 Heatsink Performance	40
5.1.2 Acoustics	40
5.1.3 Altitude	41
5.1.4 Reference Heatsink Thermal Validation	41
5.1.5 Fan Motor Performance	42
5.1.6 Pump Motor Performance	43
5.2 Environmental Reliability Testing	44
5.2.1 Structural Reliability Testing	44
5.2.1.1 Random Vibration Test Procedure	44
5.2.1.2 Shock Test Procedure	45
5.2.2 Power Cycling	46
5.2.3 Reliability Testing	46
5.2.3.1 Tubing Material Selection	48
5.2.3.2 Reservoir Sizing	48
5.2.3.3 Reliability Test Results	50
5.2.4 Recommended BIOS/CPU/Memory Test Procedures	51
5.3 Material and Recycling Requirements	52
5.4 Safety Requirements	52
5.5 Geometric Envelope for Intel Reference ATX Thermal Mechanical Design	52
5.6 Reference Attach Mechanism	54
5.7 Socket and Voltage Regulation Cooling Strategy	55
6 Intel® Quiet System Technology (Intel® QST)	57
6.1 Intel® Quiet System Technology Algorithm	57
6.1.1 Output Weighting Matrix	58
6.1.2 Proportional-Integral-Derivative (PID)	58
6.2 Board and System Implementation of Intel® Quiet System Technology	60
6.3 Intel® QST Configuration & Tuning	62

Intel QX9770 Design Guidelines - Page 12

Description, CONTROL_BASE, CONTROL - tdp

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