QX6000 Datasheet, PDF (94/98 Pages) Intel Corporation – on 65 nm Process in the 775-land LGA Package supporting Intel 64 architecture

Boxed Processor Specifications
7.3.2
7.3.3
Fan Speed Control Operation (Intel^® Core™2 Extreme
processors only)
The boxed processor fan heatsink is designed to operate continuously at full speed to
allow maximum user control over fan speed. The fan speed can be controlled by
hardware and software from the motherboard. This is accomplished by varying the duty
cycle of the Control signal on the 4th pin (see Table 32). The motherboard must have a
4-pin fan header and must be designed with a fan speed controller with PWM output
and Digital Thermometer measurement capabilities. For more information on specific
motherboard requirements for 4-wire based fan speed control refer to the appropriate
Thermal and Mechanical Design Guidelines (see Section 1.2).
The Internal chassis temperature should be kept below 39 ºC. Meeting the processor's
temperature specification (see Chapter 5) is the responsibility of the system integrator.
The motherboard must supply a constant +12 V to the processor's power header to
ensure proper operation of the fan for the boxed processor. See Table 32 for specific
requirements.
Fan Speed Control Operation (Intel^® Core™2 Quad
processor)
If the boxed processor fan heatsink 4-pin connector is connected to a 3-pin
motherboard header it will operate as follows:
The boxed processor fan will operate at different speeds over a short range of
internal chassis temperatures. This allows the processor fan to operate at a lower
speed and noise level, while internal chassis temperatures are low. If internal
chassis temperature increases beyond a lower set point, the fan speed will rise
linearly with the internal temperature until the higher set point is reached. At that
point, the fan speed is at its maximum. As fan speed increases, so does fan noise
levels. Systems should be designed to provide adequate air around the boxed
processor fan heatsink that remains cooler then lower set point. These set points,
represented in Figure 30 and Table 33, can vary by a few degrees from fan
heatsink to fan heatsink. The internal chassis temperature should be kept below
38 ºC. Meeting the processor's temperature specification (see Chapter 5) is the
responsibility of the system integrator.
The motherboard must supply a constant +12 V to the processor's power header to
ensure proper operation of the variable speed fan for the boxed processor. Refer to
Table 32 for the specific requirements.
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Datasheet