Intel ATX Power Supply Design Guide
Version 0.9
4.3 Airflow / Fan
In general, exhausting warm air from the chassis enclosure via a power supply fan at the rear panel is the preferred
It is suggested that an 80 mm ball bearing fan be used in conjunction with a thermally sensitive fan speed control circuit to balance
The intake and exhaust grills of the power supply should remain suitably free of obstruction so as not to hinder airflow or generate excessive acoustic noise (i.e. no objects within 0.5 inches of the intake or exhaust areas). The opening must be sufficiently protected to meet the safety requirements described in Section 8. For the grill pattern area relevant to a given chassis design, see Figures 2 and 3. A flush mount wire fan grill can be used instead of a stamped metal grill to maximize airflow and minimize acoustic noise.
4.4 AC Connector
The AC input receptacle should be an IEC 320 type or equivalent. In lieu of an additional switch, the IEC 320 receptacle may be considered the mains disconnect.
4.5 DC Connectors
Figure 4 shows pinouts and profiles for typical ATX power supply DC harness connectors.
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