I recently built a PC over the weekend for the first time and after turning the computer it shuts down and then powers again in a loop. We disconnected everything with the except the PSU and CPU to try and troubleshoot what exactly is happening and received the same result. We also verified that we installed the processor correctly. The processor is an AMD Ryzen 5 2600 and the motherboard is an ASRock B45OM/ac. I am unsure of where exactly we went wrong.