WiBlack Screen of Death

Hi, I’ve been having an issue with my Lenovo Legion Y520 (Windows 10) laptop. I have read about solutions in different places online but I’m hopeful someone could give me some more personal help.

Some quick backstory: some months ago after a windows update something arose where when I powered on the laptop after the startup Leno screen it would just go to a BSOD with the computer staying on and the screen still being “lit up” black, not completely turned off black, but generally just being unresponsive otherwise. I discovered that if I held the power button to switch the computer off and on again the BSOD would turn up again, but after 20 secs the login screen would load and after that everything worked fine so I didn’t really get too fussed about trying to fix it.

And then just today I got a small notice about a recommended BIOS update which I okayed. Now I can still login fine ( programs aren’t super slow but are noticeably sluggish), but after say 5-10 mins I get a randomly BSOD, with a white line at the bottom of the screen and sometimes it starts to flicker with other colours worryingly.

I can get to the advanced startup screen, but now I can’t okay system repair, restore or anything like that because it now tells me that my login password to confirm the action is incorrect. I have a pin for the startup screen instead of the stand Microsoft outlook password but I’ve checked repeatedly but the password I use is correct. When I do try and login and get to just general password settings it seems like the BSOD comes by even faster.

Said password doesn’t work in safe mode either. I can get into the BIOS menu and have noticed the default setting option, but i have read that should be a very last resort.

Could anyone else recommend a