Thermal Specifications and Design Considerations
5
Thermal Specifications and
Design Considerations
5.1
Processor Thermal Specifications
The Pentium 4 processor requires a thermal solution to maintain temperatures within
the 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
appropriate processor Thermal and Mechanical Design Guidelines (see Section 1.2).
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 (TC)
specifications when operating at or below the Thermal Design Power (TDP) value listed
per frequency in Table 26. 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
and Mechanical Design Guidelines (see Section 1.2).
The Pentium 4 processor uses a methodology for managing processor temperatures
that 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
TCONTROL, then 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 TCONTROL. 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 ensure 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. Intel has developed
a methodology for accurate power measurement that correlates to Intel test
temperature and voltage conditions. Refer to the appropriate processor Thermal and
Mechanical Design Guidelines (see Section 1.2) and the Processor Power
Characterization Methodology for the details of this methodology.
Datasheet
75
INTEL [ INTEL ]
