Screen not displaying anything at startup

[Gold9er2]

About 1 week ago my laptop went through a serious upgrade which started by itself. About 3 days after the screen wouldnt show anything. Just a weak flicker at startup.

What i have did option#1:

1. Disconnected power cable

2.removed the battery.(i had to go inside the laptop to remove it)

3.press and hold power button for 15 seconds

4. Reconnect power adapter. Did not reinstall battery

5.turn on laptop

After i did this i got the message on the screen: 

"The cmos checksum is invalid. the cmos will be reset to the default configuration and will be rebooted" "please check your bios setup options to see if they change"

I restarted the laptop and the screen is still black

What i did option #2:

1.Turn on laptop with battery out

2.press and hold windows key + b and power button for 1 second. Release.

3.rebooted laptop.

4.after i did this i got the message:

"Bios recovery files not found. Please plug bios recovery flash drive.

Enter-continue"

I restarted laptop. Still nothing on the screen.

Anyone knows what the problem is and what i have to to? Thanks

[Echo_Lake]

@Gold9er2

Thank you for posting on HP Support Community.

Don't worry as I'll be glad to help, 

In some cases the automatic BIOS recovery fails because of corrupted CMOS (Complementary Metal Oxide Semiconductor) data. The CMOS stores BIOS settings. Try this procedure to reset the CMOS and recover the BIOS.

1. Turn off the computer.

2. Press and hold the Windows + V keys.

3. Still pressing those keys, press and hold the Power button on the computer for 2-3 seconds, and then release the Power button, but continue pressing and holding the Windows + V keys until the CMOS Reset screen displays or you hear beeping sounds.

   At the completion of a successful CMOS Reset, a message similar to the one below displays:

   

4. Press Enter to restart the computer.

Hope this helps! Keep me posted for further assistance.
Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.