HP Pavilion laptop very dim screen at boot, even before HP logo

[ASka19]

HI!

After a normal power on of the HP Pavilion laptop ((I didn't write down the name and can't reconstruct it now, also given the problem I'm writing this post for, but it's a Pavilion laptop with a NVidia GeForce GTX video card and an AMD Ryzen 7 CPU and Bang&Olufgsen speakers, with a case very similar at first glance to a 15-ec0014nl), at boot  the laptop screen is immediately  very dim (not completely black, you can see e.g. the man silhouette of the pin  screen can be glimpsed, and when the pin is correctly inserted, pressing the Windows key opens the corresponding menu).
For a while we were able to use it with an external monitor, but trying to fix the issue, now we cannot activate it by using Windows - P combo menu.

The screen is dark from the start, you never see the HP logo, and even when entering the bios (I assume in my various attempts that I have succeeded, I seemed to glimpse the menu) the screen remains dark.

When the external monitor was usable I ran tests with HP tools and no HW problems were detected. Furthermore, the brightness was set to maximum in Windows and the relative keys on the keyboard have no effect on the laptop monitor.

Since the problem occurred after a reboot without the PC suffering any knocks, I would think of a problem in a automatic update, but now it becomes difficult to try a solution.

I've also tried a 'hard reset' by unplugging all peripherals and the power supply and holding the power button down for 15 seconds with the laptop switched off, but it had no effect.

Thank you in advance for any suggestions!

[ASka19]

I found a note, it is a HP Pavilion Gaming Laptop  - 15-ec1020nl.

Thank you again for your support!