American Megatrends MAN-759 manual Connect CPU Fan

Step 5 Connect CPU Fan

J6 (shown below) is a 3-pin berg that connects the fan on the CPU heat sink to the motherboard power.

All Pentium II CPUs are shipped with a heat sink and a CPU fan. The connector from the CPU fan usually has three leads (has red, yellow, and black leads). Connect the Red lead to Pin 2 (+12V). Make sure that you use fans that have 3 leads. The 3rd (yellow) lead should provide a tachometer output to permit the fan speed to be monitored by the onboard server management hardware. If you must use fans with only 2 leads, connect the red lead to Pin 2.

J5 and J33 Chassis Fans J5 and J33 are 3-pin bergs that attach to chassis fans. See the motherboard drawing for the J5 and J33 locations. J5 provides +12V power to the main chassis fan. J33 is the auxiliary chassis fan connector. He chassis fan should provide a tachometer output on Pin 3 so the fan speed can be monitored by the onboard server management hardware.

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