If you look at the PIN DEFINITION Manual for your motherboard, you will see the following:
"The motherboard comes with a standby power LED that 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 "
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Unfortunately the manual does a terrible just of showing where this jumper is located on the board BUT scanning the QR code from the User's Manual may provide more info.