Probook 440 G4 won't boot

[mistere1119]

My Probook lost power during a windows 10 update. The only screen I get is one with the HP logo in the middle. I have tried f10 and f11. Nothing works. Someone told me it could be the motherboard. This person told there's a reset button on the motherboard? Has anyone heard of this? I even tried a new hard drive at first thinking the hard drive was corrupted when the power died. I would greatly appreciate any help. Thanks in advance.

[WAWood]

@mistere1119 

The HP logo is contained in special code embedded into the firmware of a chip on the system board.  So that will display even if there is no disk drive in the laptop.  If you don't get any further, that is almost certainly a disk drive issue.

No -- there is no reset button on laptop system boards.  Some retail desktop motherboards have those, but not laptops.

If your PC is new enough to support UEFI, you can use these steps to test the hard drive: http://support.hp.com/us-en/document/c00439024

If not, to check the drive you have to follow these steps:
1) Press Esc key repeatedly, several times a second, while rebooting the laptop. Do NOT hold the key down, just press it over and over.
2) Eventually, you will see an HP Startup Menu
3) Press the Function key for testing the hard drive (usually F2) and let it run.