Press and hold the same PS4 power button, for approximately seven seconds until you hear two second beeps.
If you release the button after the first beep, you’ll put it in Rest Mode.
Unplugging the AC power cord while the indicator light is lit or pulsating may result in accidental data corruption.

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Locate the Power Button on your PlayStation 4.
However, the power buttons are a bit different on each console.
On your PS4 Slim, look to the left of the machine’s disc slot.

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Beneath it is a thin light strip that acts as the power indicator.

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