|OK so it's probably not due to being damaged or the hardware changed.|
I assume this is a desktop and not a laptop?
First I'd open the case and take a look at the motherboard. One of the more common reasons for motherboard failure are bad capacitors. They start bulging and often have leakage residue on the top. Here's a picture:
You can see the three bad ones there with brown leakage reside on the top. It may be hard tell from that picture but they look a lot like a soda can that you've put in the freezer for too long and it's just about ready to blow up. If you find any bad ones that may be the problem.
If everything looks OK on the motherboard I'd temporarily remove any unneeded add-on cards, remove any unneeded USB devices and disconnect the data cables on all the drives. Then start it up and see if the problem persists. Without the drives it won't boot to windows but just see if it starts up and you get the posting or logo screen. If it seems to start up OK then likely one of the disconnected items was at fault.
If you still have the problem then it may be the power suppy. If possible swap in a known working compatible power supply and see if it works then.