Laptop screen remains black when turned on, caps lock light blinking 3 times

[Ginac9]

My laptop was working fine last night, but this morning when I try to turn it on the screen remains black. I can hear some whiring happening and the caps lock light blinks 3 times every few seconds. The light by the power port also does light up when it is plugged in so I don’t think it’s a power issue (but I have no clue, it might well be). I didn’t properly turn it off last night I just closed the laptop instead of powering it off. 

Please help!

[Lil_Boy_Blue]

https://support.hp.com/us-en/document/bph07107

LED blinks 3 times

Memory

RAM Module failure.

1 Reseat the memory. NB:- See the Services Media Library for steps for your PC.

2 Check each individual memory module and swap slots.

3 Replace the memory modules causing three blinks or if the blinks follow the slots.

4 Replace the Main-Board.

3   MEMORY READ OR WRITE FAILURE

3   INSERT NEXT MEDIA VOLUME

Several possibilities, RAM being most likely.

IF POSSIBLE try this.....
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.
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