I turned off my pc. I went to turn it on again, had to push and hold several times before turned on.

[delirene]

The problem isn't with booting up.  It doesn't get that far.  I push and hold start.  It tries to turn on, the fan starts, etc. Then it turns back off.  I push and hold start again, the same result, until it finally stays on.  Then, it boots up fine and the pc works perfectly.  

When the pc restarts for updates, etc. the pc starts back up with no trouble.

[Lil_Boy_Blue]

Hi
First:- Turn off the computer, press and hold the PWR button for 4 seconds.

Then - Leave only keyboard and mouse connected, disconnect all externally connected
devices such as Docking Station, USB storage devices, displays, and printers.
Unplug the AC adapter from the computer.

Next - Press and Hold the Power button for 15 seconds to Hard Reset.
Rinse and Repeat; Re-Connect the AC adapter.

NOW begin checking/testing/proving the Hardware is fit for purpose.
Power on your PC, press ESC (repeatedly), then F2 at the prompt.
Choose System Tests (Fast Test does a 4 minute hardware check).
AND/OR
HOW DO I USE DIAGNOSTICS?

HP PC Hardware Diagnostics Windows is a Windows-based utility that allows you to run diagnostic tests to determine if the computer hardware is functioning properly. The tool runs within the Windows operating system in order to diagnose hardware failures. HP PC Hardware Diagnostics Windows comes pre-installed on new HP computers, but if not on yours, download here:-
https://www8.hp.com/us/en/campaigns/hpsupportassistant/pc-diags.html