Datasheet
99
Boxed Processor Specifications
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
Table 7-1
) 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.
Figure 7-9. Boxed Processor Fan Heatsink Set Points
Table 7-2.
Fan Heatsink Power and Signal Specifications
Boxed Processor
Fan Heatsink Set
Point (
º
C)
Boxed Processor Fan Speed
Notes
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
NOTES:
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.
-