My computer will not boot.

Okay, so I have had my computer off for a few days, last night, I plugged it in, and then the power went off. I turned it back on after that and then very shortly after turned it back off and unplugged it. Then today, I plugged it back in, and everything was working fine. Then I downloaded Google Chrome. I was browsing the internet from there, and I had several tabs loading at once, and then my computer just turned off. Although, the LED light was still on, as well as the monitor. I have tried unplugging everything and when turning it on, the LED light turns on, but the fans do not seem to spin and I can not even get to the Start Up screen. Any advice as to what I can do?