Intel E5400 AT80571PG0682ML Data Sheet

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Datasheet

If the boxed processor fan heatsink 4-pin connector is connected to a 4-pin 

motherboard header and the motherboard is designed with a fan speed controller with 

PWM output (CONTROL see 

capability the boxed processor will operate as follows:

As processor power has increased the required thermal solutions have generated 

increasingly more noise. Intel has added an option to the boxed processor that allows 

system integrators to have a quieter system in the most common usage.

The 4th wire PWM solution provides better control over chassis acoustics. This is 

achieved by more accurate measurement of processor die temperature through the 

processor's Digital Thermal Sensors (DTS) and PECI. Fan RPM is modulated through the 

use of an ASIC located on the motherboard that sends out a PWM control signal to the 

4th pin of the connector labeled as CONTROL. The fan speed is based on actual 

processor temperature instead of internal ambient chassis temperatures.

If the new 4-pin active fan heat sink solution is connected to an older 3-pin baseboard 

processor fan header, it will default back to a thermistor controlled mode, allowing 

compatibility with existing 3-pin baseboard designs. Under thermistor controlled mode, 

the fan RPM is automatically varied based on the Tinlet temperature measured by a 

thermistor located at the fan inlet.

For more details on specific motherboard requirements for 4-wire based fan speed 

control, refer to the appropriate Thermal and Mechanical Design Guidelines (see 

).

X ≤ 30

When the internal chassis temperature is below or equal to 
this set point, the fan operates at its lowest speed. 
Recommended maximum internal chassis temperature for 
nominal operating environment.

1

1. Set point variance is approximately ± 1 °C from fan heatsink to fan heatsink.

Y = 35

When the internal chassis temperature is at this point, the fan 
operates between its lowest and highest speeds. 
Recommended maximum internal chassis temperature for 
worst-case operating environment.

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Z ≥ 38

When the internal chassis temperature is above or equal to 
this set point, the fan operates at its highest speed.

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