Boxed Processor Specifications
102 Dual-Core Intel® Xeon® Processor 3000 Series Datasheet
Notes:
1. Set point variance is approximately ± 1 ° C from fan heatsink to fan heatsink.
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 temperature diode (T-diode). 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 see the Dual-Core Intel
®
Xeon
®
Processor 3000 Series Thermal and Mechanical
Design Guide.
§
Table 7-2. Fan Heatsink Power and Signal Specifications
Boxed Processor Fan
Heatsink Set Point (°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
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 ≥ 38 When the internal chassis temperature is above or equal to this set
point, the fan operates at its highest speed.
-
