laptop screen goes blank, what is the cause?

Hey all,

I was working on this laptop when quite often, after startup or in the middle of something (random), the screen goes blank and flickers, with random lines, etc. but you can't see anything.

When I am able to actually see because the problem hasn't started yet, everything works fine, no slowdowns, etc.

Moving the lid does nothing to alleviate the problem.

What is the potential causes? GPU? Battery? HDD? I did a BIOS test that said the HDD needed to be replaced. Laptop is older, back in the times of Vista. But I don't think it is the OS because this happens right at boot sometimes, other times at the logon screen, and others while inside.

Let me know, I'd appreciate it! Thanks

Also, when the battery is in use and plug removed, the flickering screen goes completely blank, and when I plug in again, it is back to the flickering. Forgot to mention that part.

Reportedly, the laptop died. In any case, it was trashed. Marking as solved.