Computer not booting

[Chopstick334]

So it started when my computer just shut off and wouldn't start back up. Checked all the connections and stuff, nothing. New motherboard and cpu later, the lights on my motherboard light up, but when I press the powerbutten nothing happens. So I got a new psu. Plugged everything back in and tuned it in, motherboard lights light up. Press power button, still nothing. I dont even know what could be wrong at this point. Please help.

[PhenixFel]

Does the mobo have a troubleshooting beeping speaker or a number screen? Usually you can troubleshoot depending with what noise or number it gives you. I'd recommend getting a diagnostic lil speaker that you can connect to the mobo.