Intel QX6700 HH80562PH0678M User Manual

Datasheet

95

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 

) and remote thermal diode measurement 

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.

º

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.

-

Z ≥ 39

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

-

Lower Set Point

Lowest Noise Level

Internal Chassis Temperature (Degrees C)

X

Y

Z

Increasing Fan
Speed & Noise

Higher Set Point

Highest Noise Level