AMD 64 Laptop User Manual


 
Builder’s Guide for AMD Athlon™ 64 Processor-Based
Desktops and Workstations
31684 Rev. 3.00 September 2004
4.1.2 Basic Chassis Selection Guidelines
The following are some basic guidelines to aid in finding an enclosure with adequate cooling
capability:
Use 80 mm fans or larger.
Choose a chassis with a fan in the back that is in addition to the processor fan.
Cables inside the enclosure can cause airflow disruptions. Using cable ties, tie and route the
cables out of the path of the cooling airflow.
For tower chassis, choose a chassis with power supplies that have both ATX-style bottom air
intake vents and front air intake vents.
When the system is in a tower chassis, there must be clear space in front of the chassis to allow
cool airflow in and space behind the chassis for the heated air to flow out.
Rear fans should exhaust air in the same direction—out the back of the chassis.
Front intake fans may not be of significant benefit to cooling a tower chassis, and should not
be relied upon as the sole fan in a system.
Testing done by the AMD thermal engineers has shown that the airflow pattern in is
more desirable than the airflow pattern seen in on page 25.
Figure 20
Figure 21
When the bottom inlet power supply is used, nearly all the air flows near or through the area of
the processor. As a result, the processor remains cooler.
4.1.3 Power Supply Considerations
Because heatsinks are heat radiators, like the radiator in an automobile, they need airflow to
function properly. Figure 20 on page 25 shows desirable airflow through a chassis. Desirable
configurations use a bottom-inlet power supply.
24 Hardware Considerations
Chapter 4