PSFAN Connector       Show Part Numbers       Hide Part Numbers 2503985, 2503986, 2504230, 2504937, 2504939, 2504940, 2505085, 2505087, 2505088, 2505089, 2505276, 2505675, 2506135, 2506140, 2506141, 4000447 A keyed, 3-pin connector from the power supply connects here and allows the computer software to control the fan, turning it on or off, thus overriding the power connector. The Fan Always On field overrides APM fan control. The APM fan control turns the fan off any time the computer enters a power-managed state. Set to the Yes option, the fan remains on any time the computer is on or in an APM state. If SCSI devices are dectected in the computer, the fan remains on.