Asus Rampage III Gene - Manual (Page 30)

7. Q LED
Q LEDs check key components (CPU, DRAM, VGA card, and booting
devices) in sequence during motherboard booting process. If an error is
found , the corresponding LED will continue lighting until the problem is
solved. This user-friendly design provides an intuitional way to locate the root
problem within a second.
2-6 Chapter 2: Hardware information