Processors
Intel® Pentium® 4 Processors
Thermal Management for Intel® Pentium® 4 Processors in the 478/423 Pin Package

Contents

Note This information covers thermal management for Boxed Intel® Pentium® 4 Processors in both the 478-pin and 423-pin packages.

Introduction
Systems using Intel® Pentium® 4 Processors all require thermal management. This document assumes a general knowledge of and experience with system operation, integration, and thermal management. Integrators who follow the recommendations presented can provide their customers with more reliable systems and will see fewer customers returning with thermal management issues. (The term "boxed Intel Pentium 4 Processors" refers to processors packaged for use by system integrators.)

Thermal management in boxed Intel Pentium 4 Processor-based systems can affect both the performance (Thermal Monitor feature) and noise level (variable speed fan) of the system.

The Intel Pentium 4 Processor uses the Thermal Monitor feature to protect the processor during times where the silicon would otherwise operate above specification. The feature is intended to help prevent long-term reliability damage to the processor and provide protection for unusual circumstances like higher than normal internal chassis temperatures (and inlet air temperature, defined as the air temperature entering the processor fan heatsink) or failure of a system thermal management component (such as a system fan). In its active state, the Thermal Monitor feature scales back processor power consumption, if the factory programmed thermal design temperature is exceeded. While the Thermal Monitor feature is active, the system's performance may drop below its normal peak performance level. It is critical that systems be designed to maintain low enough internal chassis and processor inlet air temperatures to prevent the Intel Pentium 4 Processor from entering a Thermal Monitor active state. In a properly thermal managed and designed system, the Thermal Monitor feature should never become active. It is recommended that the internal chassis temperature for boxed Intel Pentium 4 Processor-based systems remain below the lower set point for nominal operating environments, as shown in Table 1 and Figure 1.

In addition to the Thermal Monitor feature, the boxed Intel Pentium 4 Processor fan heatsink uses a high quality variable speed fan which allows the processor to remain within its operating thermal specifications by running at different speeds over a short range of internal chassis temperatures. The processor fan operates at a low speed while internal chassis temperatures are low. If internal chassis temperatures increase beyond a lower set point, the fan speed will rise linearly with the internal chassis temperature until the higher set point is reached. As fan speed increases, so does the noise that the fan generates. Systems should be designed to provide air around the boxed processor fan heatsink that remains below the lower set point. These set points, represented in Table 1 and Figure 1 can vary by a few degrees from fan heatsink to fan heatsink.

Table 1. Boxed Processor Fan Heatsink Set Points

For Boxed Intel Pentium 4 Processors in the 423-pin Package:
Internal Chassis Temperature (oC) Boxed Processor Fan Heatsink Set Points
X < = 361 Lower Set Point: Fan speed constant at lowest fan speed. Recommended temperature for nominal operating environment.
Y = 401 Recommended maximum internal chassis temperature for boxed Intel Pentium 4 Processor-based systems.
X > = 451 or greater Higher Set Point: Fan speed constant at highest fan speed.
For Boxed Intel Pentium 4 Processors in the 478-pin Package at 2.80 GHz (and below):
Internal Chassis Temperature (oC) Boxed Processor Fan Heatsink Set Points
X < = 331 or less Lower Set Point: Fan speed constant at lowest fan speed. Recommended temperature for nominal operating environment.
Y = 401 Recommended maximum internal chassis temperature for boxed Intel Pentium 4 Processor-based systems.
X > = 431 or greater Higher Set Point: Fan speed constant at highest fan speed.
For Boxed Intel Pentium 4 Processors in the 478-pin Package at 3 GHz (and above):
Internal Chassis Temperature (oC) Boxed Processor Fan Heatsink Set Points
X < = 321 or less Lower Set Point: Fan speed constant at lowest fan speed. Recommended temperature for nominal operating environment.
Y = 381 Recommended maximum internal chassis temperature for boxed Intel Pentium 4 Processor-based systems.
X > = 401 Higher Set Point: Fan speed constant at highest fan speed.
1Set point variance is approximately ±1°C from fan heatsink to fan heatsink.

Internal Chassis Temperature

Figure 1. Internal Chassis Temperature Impact On Noise

Allowing processors to operate at temperatures beyond their maximum specified operating temperature may shorten the life of the processor and can cause unreliable operation. Meeting the processor's temperature specification is ultimately the responsibility of the system integrator. When building quality systems using the boxed Intel Pentium 4 Processor, it is imperative to carefully consider the thermal management of the system and verify the system design with thermal testing. This document details specific thermal requirements of the boxed Intel Pentium 4 Processor. System integrators using the boxed Pentium 4 Processor should become familiar with this document.

Thermal management
Proper "thermal management" depends on two major elements: a heatsink properly mounted to the processor, and effective airflow through the system chassis. The ultimate goal of thermal management is to keep the processor at or below its maximum operating temperature.

Proper thermal management is achieved when heat is transferred from the processor to the system air, which is then vented out of the system. Boxed Intel Pentium 4 Processors are shipped with a high-quality variable speed fan heatsink, which can effectively transfer processor heat to the system air. It is the responsibility of the system integrator to ensure adequate system airflow.

Installing the fan heatsink
The fan heatsink included with the boxed Intel Pentium 4 Processor must be securely attached to the processor. Thermal interface material (either attached to the bottom of the heatsink or applied during system integration with an applicator) provides effective heat transfer from the processor to the fan heatsink. The fan cable provides power to the fan by connecting to a motherboard-mounted power header and also allows the fan to provide fan speed information to the motherboard. (Only motherboards with hardware monitoring circuitry can use the fan speed signal.) Be sure to follow the installation procedures documented in the boxed processor manual and the Integration Overview (for the boxed Intel Pentium 4 Processor in the 423-pin package or the boxed Intel Pentium 4 Processor in the 478-pin package).

The fan is a high-quality ball bearing fan that provides a good local air stream. This air stream transfers heat from the heatsink to the air inside the system. However, moving heat to the system air is only half the task. Sufficient system airflow is also needed in order to exhaust the air. Without a steady stream of air through the system, the fan heatsink will re-circulate warm air, and therefore may not cool the processor adequately.

Thermal interface material replacement for fan heatsink
Thermal interface material is required for proper heat transfer from the processor to the fan heatsink. The boxed Intel Pentium 4 Processor will have thermal interface material attached to the bottom of the heatsink or will be supplied with thermal interface material included in an applicator.

  • Thermal interface material attached to the heatsink
    Intel does not recommend the removal of the thermal interface material located on the bottom of the boxed processor fan heatsink. Removal of this material may cause damage to the processor and will void the boxed processor warranty. If you must remove and re-use the fan heatsink, it will require replacement. Also, if the thermal interface material is at all damaged, you must replace the thermal interface material or the fan heatsink. Contact Intel Customer Support for assistance.
  • Thermal interface material in an applicator
    Using the boxed processor without properly applying the included thermal interface material may cause damage to the processor and will void the boxed processor warranty. If you must remove and re-use the fan heatsink, a new application of thermal interface material is required. Contact Intel Customer Support to receive additional thermal interface material in an applicator.
Chassis recommendations
Systems based on the Intel Pentium 4 Processor in the 478-pin package must use chassis that comply with the ATX specification (revision 2.01 or later) or microATX specification (revision 1.0 or later), depending on the motherboard form factor. Intel recommends system integrators using ATX form factor motherboards to choose a chassis that complies with the ATX specification (revision 2.01 or later). Likewise, system integrators using microATX form factor motherboards should choose a chassis that complies with the microATX specification (1.0 or later).

The chassis must also support a lower internal ambient temperature than many standard ATX and microATX desktop chassis. The internal chassis temperature for systems based on Intel Pentium 4 Processors 2.80 GHz (and below) should be maintained at 40°C (or lower) for chassis in the maximum expected external ambient (which is typically 35°C). The internal chassis temperature for systems based on Intel Pentium 4 Processors 3 GHz (and above) should be maintained at 38°C (or lower) for chassis in the maximum expected external ambient (which is typically 35°C). Most chassis designed for the Pentium 4 Processor use extra internal chassis fans to improve airflow. It is strongly recommended that system integrators perform thermal testing on the chassis selected for each configuration of Intel Pentium 4 Processor-based systems, even when using a chassis on the tested chassis list.

Chassis that ship with installed power supplies must support either the ATX12V or SFX12V design guidelines.

Note System integrators must use an ATX chassis that has been specifically designed to support the boxed Intel Pentium 4 Processor in the 478-pin package. For more information about chassis that support the boxed Intel Pentium 4 Processor in the 478-pin package, review the Integration Overview for Systems based on the boxed Intel Pentium 4 Processor in the 478-pin Package. Chassis specifically designed to support the Intel Pentium 4 Processor in the 478-pin package will ship with proper mechanical and electrical support for the processor, in addition to having improved thermal performance.

Intel® Pentium® 4 Processor thermal specifications
The Intel Pentium 4 Processor datasheet (also listed in Table 2) lists the power dissipation of Intel Pentium 4 Processors at various operating frequencies. For Intel Pentium 4 Processors, the highest frequency processor available will dissipate more power than lower frequencies. When building systems that will feature many operating frequencies, testing should be performed using the highest frequency processor supported, because it dissipates the most power. System integrators can perform thermal testing using thermocouples to determine the temperature of the processor's integrated heat spreader (see Intel Pentium 4 Processor in the 423-pin Package Thermal Design Guidelines and Intel Pentium processor in the 478-pin Package Thermal Design Guidelines, for details).

A simple evaluation of the temperature of the air entering the fan heatsink can provide confidence in the system's thermal management. For boxed Intel Pentium 4 Processors, the testing point is at the center of the fan hub, approximately 0.3 inches above the fan. Evaluation of test data makes it possible to determine if a system has sufficient thermal management for the boxed processor. Systems based on Intel Pentium 4 Processors 2.80 GHz (and below) should have a maximum expected temperature of 40°C in the maximum expected external ambient (which is typically 35°C). Systems based on Intel Pentium 4 Processors 3 GHz (and above) should have a maximum expected temperature of 38°C in the maximum expected external ambient (which is typically 35°C).

DISCLAIMER: The following Temperature Conversion tool is not intended for use in engineering, architecture, or software design. It is only provided as a convenience for Intel customers. This tool is provided "AS IS," and possibly with faults. INTEL DISCLAIMS ALL WARRANTIES REGARDING THE TOOL, INCLUDING, WITHOUT LIMITATION, ALL WARRANTIES AS TO ITS ACCURACY OR UTILITY.

Table 2. Boxed Intel Pentium 4 Processor Thermal Specifications

Processor Core Frequency (GHz) Processor Package Maximum Case Temperature (oC) Maximum Recommended Fan Inlet Temperature
(oC)
Processor Thermal Design Power (W) Notes
1.30 423-pin OOI 69 40 48.9 1, 3, 5
1.30 423-pin OOI 70 40 51.6 1, 3, 6
1.40 423-pin OOI 70 40 51.8 1, 3, 5
1.40 423-pin OOI 72 40 54.7 1, 3, 6
1.40 478-pin FC-PGA 72 40 55.3 2, 4, 6
1.40 478-pin FC-PGA 72 40 55.3 2, 4, 7
1.50 423-pin OOI 72 40 54.7 1, 3, 5
1.50 423-pin OOI 73 40 57.8 1, 3, 6
1.50 423-pin OOI 73 40 57.8 1, 3, 7
1.50 478-pin FC-PGA2 73 40 57.9 2, 4, 6
1.50 478-pin FC-PGA2 73 40 57.9 2, 4, 7
1.50 478-pin FC-PGA2 71 40 62.9 2, 4, 7, 10
1.60 423-pin OOI 75 40 61.0 1, 3, 6
1.60 423-pin OOI 75 40 61.0 1, 3, 7
1.60 478-pin FC-PGA2 75 40 60.8 2, 4, 6
1.60 478-pin FC-PGA2 75 40 60.8 2, 4, 7
1.60A 478-pin FC-PGA2 66 40 46.8 4, 8, 9, 10
1.70 423-pin OOI 76 40 64.0 1, 3, 6
1.70 423-pin OOI 76 40 64.0 1, 3, 7
1.70 423-pin FC-PGA2 76 40 63.5 2, 4, 6
1.70 478-pin FC-PGA2 76 40 63.5 2, 4, 7
1.70 478-pin FC-PGA2 73 40 67.7 2, 4, 7, 10
1.80 423-pin OOI 78 40 66.7 1, 3, 6
1.80 423-pin OOI 78 40 66.7 1, 3, 7
1.80 478-pin FC-PGA2 77 40 66.1 2, 4, 6
1.80 478-pin FC-PGA2 77 40 66.1 2, 4, 7
1.80A 478-pin FC-PGA2 67 40 49.6 4, 8, 9, 10
1.90 423-pin OOI 73 40 69.2 1, 3, 7
1.90 478-pin FC-PGA2 75 40 72.8 2, 4, 7
2 423-pin OOI 74 40 71.8 1, 3, 7
2 478-pin FC-PGA2 76 40 75.3 2, 4, 7
2A 478-pin FC-PGA2 68 40 52.4 4, 8, 9
2.20 478-pin FC-PGA2 69 40 55.18 4, 8, 9
2.26 478-pin FC-PGA2 70 40 56.0 4, 8, 9
2.40 478-pin FC-PGA2 70 40 57.8 4, 8, 9
2.40A 478-pin FC-PGA2 69.1 38 89 4
2.40B 478-pin FC-PGA2 71 40 59.8 4, 8, 11
2.40C 478-pin FC-PGA2 74 40 66.2 4,8,15
2.50 478-pin FC-PGA2 72 40 61.0 4, 8, 11
2.53 478-pin FC-PGA2 71 40 59.3 4, 8, 9
2.53 478-pin FC-PGA2 72 40 61.5 4, 8, 11
2.60 478-pin FC-PGA2 72 40 62.6 4, 8, 11
2.60C 478-pin FC-PGA2 75 40 69.0 4,8,15
2.66 478-pin FC-PGA2 74 40 66.1 4, 8, 11
2.80 478-pin FC-PGA2 75 40 68.4 4, 8, 11
2.80A 478-pin FC-PGA2 69.1 38 89 4
2.80C 478-pin FC-PGA2 75 40 69.7 4,8,15
2.80E 478-pin FC-PGA2 69.1 38 89 4
3 478-pin FC-PGA2 70 38 81.9 4, 8, 13, 14

3E

478-pin FC-PGA2

69.1

38

89

4

3.06 478-pin FC-PGA2 69 38 81.8 4, 8, 12, 13
3.20 478-pin FC-PGA2 70 38 82.0 4, 8, 13, 14

3.20E

478-pin FC-PGA2

73.2

38

103

4

3.40

478-pin FC-PGA2

70

38

82

4, 8, 13, 14

3.40E

478-pin FC-PGA2

73.2

38

103

4

Notes
  1. These specifications are from the Intel® Pentium® 4 Processor in the 423-pin Package Datasheet.
  2. These specifications are from the Intel® Pentium® 4 Processor in the 478-pin Package Datasheet.
  3. This processor is in the 423-pin OLGA on Interposer (OOI) package.
  4. This processor is in the 478-pin FC-PGA2 package.
  5. These specifications apply to processors based on the B2 stepping (1.70V).
  6. These specifications apply to processors based on the C1 stepping (1.75V).
  7. These specifications apply to processors based on the D0 stepping (1.75V).
  8. These specifications are from the Intel Pentium® 4 Processor with 512KB L2 Cache on 0.13 Micron Process Datasheet.
  9. These specifications apply to processors based on the B0 stepping (1.50V).
  10. Some processors at this frequency have specifications that differ from those in the datasheet. These parts are distinguishable by their S-Spec number. Refer to the Intel® Pentium® 4 Processor Specification Update and the Product Specifications and Comparisons tool for the detailed specifications and for the specific S-Specs associated with these different specifications.
  11. These specifications apply to processors based on the C1 stepping (1.525V).
  12. These specifications apply to processors based on the C1 stepping (1.550V).
  13. Some processors at this frequency have different VIDs. These specifications are based on the highest VID for this processor frequency. See the Intel® Pentium® 4 Processor Datasheet for details.
  14. These specifications apply to processors based on the D1 stepping (1.550V).
  15. These specification apply to processor based on the D1 stepping (1.525V).

This applies to:

Intel® Pentium® 4 Processor Extreme Edition
Intel® Pentium® 4 Processors



Solution ID: CS-007999
Last Modified: 26-Sep-2014
Date Created: 22-Dec-2003
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