Intel Pentium 4 Processor Extreme Edition on 0.13 Micron Process in the 775-Land Package Datasheet

84 Datasheet

Boxed Processor Specifications

7.3 Thermal Specifications

This section describes the cooling requirements of the fan heatsink solution used by the boxed

processor.

7.3.1 Boxed Processor Cooling Requirements

The boxed processor may be directly cooled with a fan heatsink. However, meeting the processor's

temperature specification is also a function of the thermal design of the entire system, and

ultimately the responsibility of the system integrator. The processor temperature specification is

found in Chapter 5. The boxed processor fan heatsink is able to keep the processor temperature

within the specifications (see Table 5-1) in chassis that provide good thermal management. For the

boxed processor fan heatsink to operate properly, it is critical that the airflow provided to the fan

heatsink is unimpeded. Airflow of the fan heatsink is into the center and out of the sides of the fan

heatsink. Airspace is required around the fan to ensure that the airflow through the fan heatsink is

not blocked. Blocking the airflow to the fan heatsink reduces the cooling efficiency and decreases

fan life. Figure 7-7 and Figure 7-8 illustrate an acceptable airspace clearance for the fan heatsink.

The air temperature entering the fan should be kept below 38 °C. Again, meeting the processor's

temperature specification is the responsibility of the system integrator.

Note: The processor fan is the primary source of airflow for cooling the Vcc voltage regulator. Dedicated

voltage regulator cooling components may be necessary if the selected fan is not capable of

keeping regulator components below maximum rated temperatures.

Figure 7-6. Baseboard Power Header Placement Relative to Processor Socket

R4.33

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