Computer gives no warning, just shuts down

[JesseBernier]

I am wanting to figure out if someone can help me.  My Probook 455 G1 keeps shutting down randomly I replaced the A/C power adapter and the battery and I am still having it happen 

[IT_WinSec]

Hello @JesseBernier

Welcome to the HP Support forum.

Does it just shut down OR it restarts after that ? How often did this happen ? When did it start ?

** If your PC shuts off with a warning from Windows (some message on screen), then this is software issue and is connected to Windows (e.g. Windows Update) , some 3rd party software (good or bad).

** If the PC shuts down without any warning, it could be hardware issue.

Please, check this article for reasons for the PC to turn off unexpectedly - could be motherboard, battery, overheating, etc....

>> http://www.computerhope.com/issues/ch000689.htm

>> https://support.hp.com/us-en/document/c01657439

Follow the instructions in the articles. Also download and run the free Speccy to check the hardware's temperature > http://www.piriform.com/speccy

 Please, perform some basic hardware checks

1. Please, shutdown the computer using the power button

2. Power it on.

2.1 As soon as you press the power-on button, immediately begin hitting the Esc button (like tap-tap-tap).

This should open a HP Startup Menu which may look similar to this one

3. Choose F2 to open System Diagnostics. Follow the on-screen instructions to perform System Test >> Quick test.

This will check major hardware componets for issue (do it just in case) . Here is more info >> https://www.youtube.com/watch?v=6JXUp43ahHA

If there are no system checks/no quick tests, perform HDD and RAM check.

If there is a Component tests, you may also test the Motherboard and battery

Let me know the test results.

Please, let me know the results from Speccy (temp), how is your battery performing and provide an update.