Is my PSU dead?

[DONR]

I'll try to keep this as simple as possible.

My PC was working fine all day yesterday. This morning I try to turn it on, and nothing happens, at all.

My PC is plugged into a special multi socket that is supposed to protect from lightning strikes and overcharges, which that is plugged into a mechanical time switch socket that turns on/off power at a set time, and that time switch is then in the actual wall socket.

This morning I heard a loud bang when the time socket flipped on, I didn't think anything of it, but found out that the fuse box jumped out, or however you want to call that.

I flicked my fuse back on, went to turn my PC back on, and it's dead. All my other  hardware such as monitor, modem, surround sound system are also plugged into that same multi socket, they all still work.

My PSU is a Corsair HX1000, I have now taken the PSU completely out of my PC, and unhooked all cables. I have seen that paperclip trick from a Google search, to see if my PSU is still working, but all the cables are black, so I cannot really bridge anything that way.

I have now plugged in the cables for my motherboard into my PSU, and the power cable into a different wall socket, and flipped the power switch of the PSU on, but still nothing. I can't really plug in a single fan either, since all fans are plugged into the motherboard.

I'm not super knowledgeable in terms of PC Hardware, I've never built my own, and I'm honestly not sure if I can put all the cables back into my PSU in the correct order that I took them out, but I do have some knowledge, as you could read, so please bare that in mind.

I'm not sure what to do now. Taking my PSU out, I also noticed that something loose is in there, sounds like a small piece of plastic that makes noise every time I turn the PSU upside down. I never took my PSU out, so I don't know if that was there before.

I hope someone can help me, thank you.