Active Tower Thermal Solution

Figure 10-3. Physical Space Requirements for the Solution (top view)

Note: Diagram does not show the attached hardware for the clip design and is provided only as a mechanical representation.

10.2.2Retention Mechanism and Heatsink Attach Clip Assembly

The thermal solution requires a heatsink attach clip assembly, to secure the processor and fan heatsink in the baseboard socket.

10.3Electrical Requirements

10.3.1Active Tower Heatsink Power Supply

The active tower heatsink requires a +12 V power supply. A fan power cable will be with solution to draw power from a power header on the baseboard. The power cable connector and pinout are shown in Figure 10-4. Baseboards must provide a matched power header to support this. Table 10-1contains specifications for the input and output signals at the heatsink connector.

The active tower heatsink outputs a SENSE signal, which is an open- collector output that pulses at a rate of 2 pulses per fan revolution. A baseboard pull-up resistor provides VOH to match the system board-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.

The fan heatsink receives a PWM signal from the motherboard from the 4th pin of the connector labeled as CONTROL.

The active tower heatsink requires a constant +12 V supplied to pin 2 and does not support variable voltage control or 3-pin PWM control.

Thermal/Mechanical Specifications and Design Guidelines

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