PC doesn't start after getting injected 12V in USB port

Hello everyone, im a little bit confused, i just made a big mistake with my arduino card, which was supply by an external power supply on 12V when I decided to modify my code and plug the card by its USB slot.

My PC crash instantaneous 20 min ago and i dont know what can I do to fix it.

If someone could explain me I will be very greatful

Does it not start at all; not even BIOS or power on?

If I read the title, I don't give you much hope; I think that 12V into the USB will kill at least the mother board.

Which Arduino? Original or clone?

that was a clone.
After testing my computer supply, it wasnt give me any electric voltage. I hope the motherboard is fine but i dont have so much hope about it to be honest, I'm a bit angry about myself for this mistake, i hope my HDD and SDD are fine but I cant test them at the moment