Asus P8Z77 WS - Manual (Page 37)

ASUS P8Z77 WS 2-15
Chapter 2
3. EPU LED
The EPU LED lights when the EPU switch is turned to
Enable.
4. Q-Code LEDs
The Q-Code LED design provides you the 2-digit display, allowing you to know the
system status. Refer to the Q-Code table below for details.