Alright, so I bought a Lenovo Y545 real cheap on eBay because it was marked as broken, and what do you know, it's actually broken. Typically these broken laptops aren't too bad to fix but I'm having real issues with this one. It took me days of trying, but I was finally able to get it from a state where it would constantly bluescreen on boot up no matter what (or kernel panic if booting into Linux) and managed to get the BIOS updated to the latest version, and now it will boot consistently.
However, it will only boot consistently with the power cable not plugged in. If I try to boot with the power cable plugged in it BSOD's, if I boot into windows and log in without it connected it works, but will BSOD within a minute or less if I plug the cable in.
Typically the BSOD message is saying it has some problem with ACPI.sys, and SYSTEM_THREAD_EXCEPTION_NOT_HANDLED.
Is it possible the BIOS is still corrupt? Am I dealing with hardware damage?