http://pinouts.ru/Power/atxpower_pinout.shtml
| Pin | Name | | Color | Description |
|---|---|---|---|---|
| 1 | 3.3V | Orange | +3.3 VDC | |
| 2 | 3.3V | Orange | +3.3 VDC | |
| 3 | COM | Black | Ground | |
| 4 | 5V | Red | +5 VDC | |
| 5 | COM | Black | Ground | |
| 6 | 5V | Red | +5 VDC | |
| 7 | COM | Black | Ground | |
| 8 | PWR_OK | Gray | Power Ok (is a status signal generated by the power supply to notify the computer that the DC operating voltages are within the ranges required for proper computer operation) | |
| 9 | 5VSB | Purple | +5 VDC Standby Voltage (max 10mA) | |
| 10 | 12V | Yellow | +12 VDC | |
| 11 | 3.3V | Orange | +3.3 VDC | |
| 12 | -12V | Blue | -12 VDC | |
| 13 | COM | Black | Ground | |
| 14 | /PS_ON | Green | Power Supply On (active low). Short this pin to GND to switch power supply ON, disconnect from GND to switch OFF. | |
| 15 | COM | Black | Ground | |
| 16 | COM | Black | Ground | |
| 17 | COM | Black | Ground | |
| 18 | -5V | White | -5 VDC | |
| 19 | 5V | Red | +5 VDC | |
| 20 | 5V | Red | +5 VDC |
/PSON activated by pressing and releasing the power button while the power supply is in standby mode. Activating /PSON connects the power supply’s /PSON input to ground, thereby switching the power supply to full-on condition.