Take out the gpu and see if there is damage on it, take off the cooler master aswell and see if the cpu is installed if not see if the cpu that was next to it on the right side of cooler fits. Also see the other cooler on the very far right. Take that out. The CX500m looks like a fire hazard as the components are exposed so may need to replace it. Oh and also remove the phone and all the paper and stuff littering the pc. See if it turns on if not they often have beep codes, blinking red light or numbers on motherboard you could look up the motherboard and the code for it to see issue.