Thermally Advantaged Small Chassis (TASC) Design Guide
Introduction
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1 Introduction
1.1 Scope
This design guide explores the generic application of chassis features (vents and fans)
to adequately cool the internal components of a small form factor personal computer
with an Intel Mini ITX motherboard. Design recommendations are presented for
implementation within mini desktop and mini tower style enclosures with CPU TDP
below 95 Watts. The target audiences for this document are: computer enclosure
engineers, designers, and system integrators. This document is intended to facilitate
the thermal design of small form factor chassis intended for the use of Intel’s
mainstream Mini-ITX socketed motherboards. It is not specifically optimized solution
for Intel’s Low Cost Intel Architecture based Mini-ITX motherboards.
1.2 Overview
Small form factor has been evolving quickly in the last several years and expected to
continue at a fast pace. The mATX platform has been reduced in size reaching its
minimum at around 10 Liters, with smaller options even available using mobile
components. As this size limitation is pushed, Intel has adopted the mini-ITX board
size specified by Via Technologies, Inc. As the chassis size can now be reduced
greatly between 4 and 8 Liters (depending on feature set and components), this
design guide is intended to aide in satisfying thermal requirements for Intel’s 2008
mini ITX platform and beyond for this size range.
Proper thermal management of PC enclosure design is critical to the performance and
functionality of internal PC components as well as achieving desirable acoustic noise
levels. There are many different ways to provide proper chassis thermal management.
The design approach described in the document is one such method that if
implemented correctly will provide a single, cost effective solution for a wide range of
PC platform generations.
Recommendations are based on these considerations:
Address the 2009 platform CPU location change and remove the dependency
on CPU location entirely
Generic application to small form factor chassis sizes 4-8 liters
Maintain relaxation of the FHS inlet ambient spec from 39C to 40 C
Not impose ducting, baffles, or other cost adders to the chassis
Attempt to optimize chassis thermal performance for all critical areas, not just
the CPU inlet temperature.