Computer shuts off after turning it on

I recently unplugged my computer and held the power button down as a means to try to fix a plrevious problem i had with my monitor, mouse, and keyboard not responding to my computer being turned on and what ended up happening is whenever i turn my computer on it will run for a second, then shut off. The fans run and then stop along with the power, so i know that its ninot an overheating problem (maybe)