Intel 845GE, Руководство по тепловому проектированию

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Introduction
R
Intel
®
845GE / 845PE Chipset (G)MCH Thermal Design Guide 7
1 Introduction
As the complexity of computer systems increases, so do power dissipation requirements. Care
must be taken to ensure that the additional power is properly dissipated. Heat can be dissipated
using improved system cooling, selective use of ducting, and/or passive heatsinks.
The objective of thermal management is to ensure that the temperature of all components in a
system is maintained within functional limits. The functional temperature limit is the range
within which the electrical circuits can be expected to meet specified performance requirements.
Operation outside the functional limit can degrade system performance, cause logic errors, or
cause component and/or system damage. Temperatures exceeding the maximum operating limits
may result in irreversible changes in the operating characteristics of the component.
The simplest and most cost-effective method is to improve the inherent system cooling
characteristics of the 82845GE GMCH /82845PE MCH is through careful design and placement
of fans, vents, and ducts. When additional cooling is required, component thermal solutions may
be implemented in conjunction with system thermal solutions. The size of the fan or heatsink can
be varied to balance size and space constraints with acoustic noise.
This document is for the 845GE and 845PE chipsets. The thermal and mechanical design
guidelines are described for both the 82845GE GMCH and 82845PE MCH. For the ICH4, refer
to the Intel
®
82801DB I/O Controller Hub 4 (ICH4) Thermal Design Guidelines (document
number 298651).
The thermal design guides in this document provide an understanding of the operating limits of
the 82845GE GMCH / 82845PE MCH components and discusses a generic thermal solution.
This document presents the conditions and requirements to properly design a cooling solution for
systems that use the 82845GE GMCH / 82845PE MCH. Properly designed solutions provide
adequate cooling to maintain the (G)MCH case temperature at or below thermal specification.
This is accomplished by providing a low local-ambient temperature, ensuring adequate local
airflow, and minimizing the case to local-ambient thermal resistance. By maintaining the
(G)MCH case temperature at or below those recommended in this document, a system designer
can ensure the proper functionality, performance, and reliability of the component. Table 1
summarizes the specifications discussed in this design guide.
Note: Unless otherwise specified, the information in this document applies to both the 82845GE
GMCH and 82845PE MCH. The term (G)MCH refers to both the 82845GE GMCH and
82845PE MCH.