H p Pavilion 20 all in one flashing logo

[Popzilla210]

I actually just bought this computer from a pawn shop it has a flashing HP logo and the hard drive activity light blinks one long white blink in three short white blinks. I can hear like a how do I explain this sound like a REV up of a motor and then it's stops other than that it's a blank screen

[Riddle_Decipher]

@Popzilla210 Welcome to HP Forums Community!

There are a few steps to resolve the concern:

Perform a hard reset (All-in-Ones and Desktops)

Many startup errors and other problems can be resolved by a hard reset, which decreases the amount of power stored in hardware components.

1. Shut down the computer, then disconnect the power cord from the rear of the computer.

2. Press and hold down the power button for at least 10 seconds, then release it. The power light indicator might turn on briefly then go out.

3. Reconnect the power cord, then turn on the computer to confirm if the issue is resolved.

Perform a clear CMOS (All-in-Ones)

For All-in-One computers introduced after April 2016, follow these steps to reset computer CMOS data.

1. Turn off the computer.

2. Press and hold the Windows and the V keys.

3. While still pressing those keys, press and hold down the Power button on the computer for 2-3 seconds.

4. Release all the keys.

5. At the completion of a successful CMOS reset, a CMOS Reset (502) message displays.

6. Restart the computer.

If the symptoms persist and the computer does not start after the CMOS reset, or your computer was released before April 2016, continue troubleshooting the issue.

Disconnect all external devices and check if the device turns on, with only the keyboard, mouse and the power cord,

If the issue persists, perform a BIOS Recovery using the steps from this link: Click here

Keep us posted,

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