Intel 521 Data Sheet - Page 75

Datasheet

75

Thermal Specifications and Design Considerations

5

Thermal Specifications and

Design Considerations

5.1

Processor Thermal Specifications

The Pentium 4 processor in the 775-land package requires a thermal solution to maintain

temperatures within operating limits as set forth in

Section 5.1.1

. Any attempt to operate the

processor outside these operating limits may result in permanent damage to the processor and

potentially other components within the system. As processor technology changes, thermal

management becomes increasingly crucial when building computer systems. Maintaining the

proper thermal environment is key to reliable, long-term system operation.

A complete thermal solution includes both component and system level thermal management

features. Component level thermal solutions can include active or passive heatsinks attached to the

processor Integrated Heat Spreader (IHS). Typical system level thermal solutions may consist of

system fans combined with ducting and venting.

For more information on designing a component level thermal solution, refer to the

Intel

®

Pentium

®

4 Processor on 90 nm Process in the 775-Land Package Thermal Design Guidelines

.

Note:

The boxed processor will ship with a component thermal solution. Refer to

Chapter 7

for details on

the boxed processor.

5.1.1

Thermal Specifications

To allow for the optimal operation and long-term reliability of Intel processor-based systems, the

system/processor thermal solution should be designed such that the processor remains within the

minimum and maximum case temperature (T

C

) specifications when operating at or below the

Thermal Design Power (TDP) value listed per frequency in

Table 5-1

. Thermal solutions not

designed to provide this level of thermal capability may affect the long-term reliability of the

processor and system. For more details on thermal solution design, refer to the appropriate

processor thermal design guidelines.

The Pentium 4 processor in the 775-land package introduces a new methodology for managing

processor temperatures which is intended to support acoustic noise reduction through fan speed

control. Selection of the appropriate fan speed will be based on the temperature reported by the

processor’s thermal diode. If the diode temperature is greater than or equal to T

CONTROL

, the

processor case temperature must remain at or below the temperature as specified by the thermal

profile. If the diode temperature is less than T

CONTROL

then the case temperature is permitted to

exceed the thermal profile, but the diode temperature must remain at or below T

CONTROL

. Systems

that implement fan speed control must be designed to take these conditions into account. Systems

that do not alter the fan speed only need to guarantee the case temperature meets the thermal profile

specifications.

To determine a processor's case temperature specification based on the thermal profile, it is

necessary to accurately measure processor power dissipation.

Section	Page
Contents	3
Revision History	7
Intel® Pentium® 4 Processors 570/571, 560/561, 550/551, 540/541, 530/531, and 520/521	9
1 Introduction	11
1.1 Terminology	12
1.1.1 Processor Packaging Terminology	12
1.2 References	13
2 Electrical Specifications	15
2.1 FSB and GTLREF	15
2.2 Power and Ground Lands	15
2.3 Decoupling Guidelines	15
2.3.1 VCC Decoupling	16
2.3.2 FSB GTL+ Decoupling	16
2.3.3 FSB Clock (BCLK[1:0]) and Processor Clocking	16
2.4 Voltage Identification	17
2.4.1 Phase Lock Loop (PLL) Power and Filter	19
2.5 Reserved, Unused, FC and TESTHI Signals	20
2.6 FSB Signal Groups	21
2.7 GTL+ Asynchronous Signals	22
2.8 Test Access Port (TAP) Connection	23
2.9 FSB Frequency Select Signals (BSEL[2:0])	23
2.10 Absolute Maximum and Minimum Ratings	24
2.11 Processor DC Specifications	24
2.12 VCC Overshoot Specification	33
2.12.1 Die Voltage Validation	33
2.13 GTL+ FSB Specifications	34
3 Package Mechanical Specifications	35
3.1 Package Mechanical Drawing	35
3.2 Processor Component Keep-Out Zones	39
3.3 Package Loading Specifications	39
3.4 Package Handling Guidelines	39
3.5 Package Insertion Specifications	40
3.6 Processor Mass Specification	40
3.7 Processor Materials	40
3.8 Processor Markings	40
3.9 Processor Land Coordinates	41
4 Land Listing and Signal Descriptions	43
4.1 Processor Land Assignments	43
4.2 Alphabetical Signals Reference	66
5 Thermal Specifications and Design Considerations	75
5.1 Processor Thermal Specifications	75
5.1.1 Thermal Specifications	75
5.1.2 Thermal Metrology	79
5.2 Processor Thermal Features	79
5.2.1 Thermal Monitor	79
5.2.2 Thermal Monitor 2	80
5.2.3 On-Demand Mode	81
5.2.4 PROCHOT# Signal	82
5.2.5 THERMTRIP# Signal	82
5.2.6 TCONTROL and Fan Speed Reduction	82
5.2.7 Thermal Diode	83
6 Features	85
6.1 Power-On Configuration Options	85
6.2 Clock Control and Low Power States	85
6.2.1 Normal State	86
6.2.2 HALT and Enhanced HALT Powerdown States	86
6.2.2.1 HALT Powerdown State	86
6.2.2.2 Enhanced HALT Powerdown State	86
6.2.3 Stop-Grant State	87
6.2.4 Enhanced HALT Snoop or HALT Snoop State, Grant Snoop State	88
6.2.4.1 HALT Snoop State, Grant Snoop State	88
6.2.4.2 Enhanced HALT Snoop State	88
7 Boxed Processor Specifications	89
7.1 Mechanical Specifications	90
7.1.1 Boxed Processor Cooling Solution Dimensions	90
7.1.2 Boxed Processor Fan Heatsink Weight	91
7.1.3 Boxed Processor Retention Mechanism and Heatsink Attach Clip Assembly	91
7.2 Electrical Requirements	91
7.2.1 Fan Heatsink Power Supply	91
7.3 Thermal Specifications	93
7.3.1 Boxed Processor Cooling Requirements	93

Intel 521 Data Sheet - Page 75

Thermal Specifications and, Design Considerations

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