I didn't want to make a new thread so I replied in this one.
I have about the same problem but the thing is, by computer turns on for 3 seconds, all my fans etc turn on then the computer just turns off. Do you guys have any idea about how I can fix this. I have a 3 month old PSU that is 500W which is enough power to power what I have (sig), and it has been working fine till lately, it just shuts down randomly(it shuts down, not reboot), and now it just won't turn on.