Introduction
Thermal and Mechanical Design Guidelines 7
1 Introduction As the complexity of computer systems increases, so do power dissipation
requirements. The additional power of next generation systems must be properly
dissipated. Heat can be dissipated using improved system cooling, selective use of
ducting, and/or active/passive heatsinks.
The objective of thermal management is to ensure that the temperatures of all
components in a system are 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 goal of this
document is to provide an understanding of the operating limits of the Intel®
82945G/82945GZ/82945GC Graphics and Memory Controller Hub (GMCH) and Intel®
82945P/82945PL Memory Controller Hub (MCH), and discuss a reference thermal
solution.
The simplest and most cost-effective method to improve the inherent system cooling
characteristics of the (G)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 presents the conditions and requirements to properly design a cooling
solution for systems that implement the 82945G/82945GZ/82945GC GMCH or
82945P/82945PL MCH. Properly designed solutions provide adequate cooling to
maintain the (G)MCH case temperature at or below thermal specifications. 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
these components.
Note: Unless otherwise specified, the information in this document applies to the Intel®
82945G/82945GZ/82945GC Graphics and Memory Controller Hub (GMCH) and the
Intel® 82945P/82945PL Memory Controller Hub (MCH). The term (G)MCH refers to the
82945G GMCH, 82945GZ GMCH, 82945GC GMCH, 82945P MCH, and 82945PL MCH.
Note: Unless otherwise specified, ICH7 refers to the Intel® 82801GB ICH7 and 82801GR
ICH7R I/O Controller Hub 7 components.