Intel Xeon E5405 BX80574E5405 User Manual

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Quad-Core Intel® Xeon® Processor 5400 Series TMDG

Clearance is required around the heatsink to ensure unimpeded airflow for proper 
cooling. The physical baseboard keepout requirements for the active solution are the 
same as the passive CEK solution shown in 

. Refer to 

 through 

 for additional details on the active CEK thermal solution volumetrics.

The active heatsink includes a fan, which requires a +12 V power supply. Platforms 
must provide a matched fan power header to support the boxed processor. 

 

contains specifications for the input and output signals at the heatsink fan connector. 

The fan outputs a SENSE signal, an open-collector output, which pulses at a rate of two 
pulses per fan revolution. A baseboard pull-up resistor provides VCC to match the 
baseboard-mounted fan speed monitor requirements, if applicable. Use of the SENSE 
signal is optional. If the SENSE signal is not used, pin 3 of the connector should be tied 
to GND.

It is recommended that a 4 pin fan header be used on the baseboard, in addition to, a 
control ASIC that can send a PWM signal to the active fan heatsink solution on the 4

th

 

pin, at a nominal 25 KHz frequency. If a 3-pin CPU fan header is used instead, the 
active fan heatsink solution will revert back to an automatic ambient air temperature 
control mode.

The fan power header on the baseboard must be positioned to allow the fan heatsink 
power cable to reach it. The fan power header identification and location must be 
documented in the supplier’s platform documentation, or on the baseboard itself. The 
baseboard fan power header should be positioned within 177.8 mm [7 in.] from the 
center of the processor socket.

System board should pull this pin up to V

CC

 with a resistor.

+12V: 12 Volt Fan Power 

Supply

10.8

12

12

13.2

V

IC: Fan Current Draw

N/A

 1.25

1.5

1.5

A

SENSE: SENSE Frequency

2

2

2

2

Pulses per fan revolution

1