Asus SABERTOOTH 990FX/GEN3 R2.0 - Manual (Page 42)

1-28 Chapter 1: Product introduction
Chapter 1
1.2.8 Onboard LEDs
1. POST State LEDs
The POST State LEDs provide the status of these key components during POST
(Power-On-Self Test): CPU, memory modules, VGA card, and hard disk drives. If an
error is found, the critical component’s LED stays lit up until the problem is solved.
2. Standby Power LED
The motherboard comes with a standby power LED. The green LED lights up to
indicate that the system is ON, in sleep mode, or in soft-off mode. This is a reminder
that you should shut down the system and unplug the power cable before removing or
plugging in any motherboard component. The illustration below shows the location of
the onboard LED.