Asus Maximus III Extreme - Manual (Page 34)

6. GO LED
Blinking: Indicates that MemOK! is enabled before POST.
Lighting: Indicates that the system loads the preset profile (GO_Button file)
for temporary overclocking when in OS.
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 LED next to the error device will continue lighting until the problem
is solved. This user-friendly design provides an intuitional way to locate the
root problem within a second.
2-4 Chapter 2: Hardware information