My computer shut down and will not power up at all. There is no indication of power. I have verified all of the steps listed that I can, but no luck. The motherboard does have a green light on, but nothing else even makes a sound (fan, etc). I replaced the PSU, but nothing changed. I disconnected drives and removed RAM, but nothing changed. I cannot locate any fractures or burn marks. Should the PSU fan come on? There is literally no activity. The system does not have an internal speaker. Is it possible it might provide beeps even though there is no other activity?