Intel Pentium 4 Processor on 90 nm Process Thermal and Mechanical Design Guidelines

Introduction
R
Intel
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Pentium
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4 on 90 nm Process Thermal Design Guide 9
1 Introduction
The objective of thermal management is to ensure that the temperatures of all components in a
system are maintained within their functional temperature range. Within this temperature range, a
component, and in particular its electrical circuits, is expected to meet its specified performance.
Operation outside the functional temperature range can degrade system performance, cause logic
errors or cause component and/or system damage. Temperatures exceeding the maximum
operating limit of a component may result in irreversible changes in the operating characteristics
of this component.
In a system environment, the processor temperature is a function of both system and component
thermal characteristics. The system level thermal constraints consist of the local ambient air
temperature and airflow over the processor as well as the physical constraints at and above the
processor. The processor temperature depends in particular on the component power dissipation,
the processor package thermal characteristics, and the processor thermal solution.
All of these parameters are aggravated by the continued push of technology to increase processor
performance levels (higher operating speeds, GHz) and packaging density (more transistors). As
operating frequencies increase and packaging size decreases, the power density increases while
the thermal solution space and airflow typically become more constrained or remain the same
within the system. The result is an increased importance on system design to ensure that thermal
design requirements are met for each component, including the processor, in the system.
Depending on the type of system and the chassis characteristics, new system and component
designs may be required to provide adequate cooling for the processor. The goal of this document
is to provide an understanding of these thermal characteristics and discuss guidelines for meeting
the thermal requirements imposed on single processor systems for the entire life of the Pentium 4
processor on 90 nm process.
Chapter 3 discusses thermal solution design for the Pentium 4 processor on 90 nm process in the
context of personal computer applications. This section also includes thermal metrology
recommendation to validate a processor thermal solution. It also addresses the benefits of the
processor’s integrated thermal management logic for thermal design.
Chapter 4 provides preliminary information on the Intel reference thermal solution for the
Pentium 4 processor on 90 nm process.
Note: The physical dimensions and thermal specifications of the processor that may be used in this
document are for illustration only. Refer to the Pentium 4 processor on 90 nm process Datasheet
for the product dimensions, thermal power dissipation, and maximum case temperature. In case of
conflict, the data in the datasheet supercedes any data in this document.