Blackout error. Not as easy to diagnose as YLoD Recommend you find a trusted repair shop

I have the same model doing the same thing. It worked fine until I took it apart to clean and replace thermal paste...

Had the exact same thing happen to me I have no idea what I did wrong, only thing I know is I'm never taking anything apart ever again 💀

Could be a bunch of things but I'd first try a new power supply

Try first swapping the HDD

try hooking up the SYSCON to ur computer and get an error code