Asus P9D WS - Manual (Page 36)

2-18 Chapter 2: Hardware information
Chapter 2
5. PWR_SUPPLY LED
The ASUS Dr. Power LED near EATX PWR connector lights up when the ASUS Dr.
Power switch setting is turned to Enable and the power supply unit failed.
6. PGLED3 LED
The ASUS Dr. Power LED near the ASUS Dr. Power switch lights up when the ASUS
Dr. Power switch is turned to enable.