Question PC won't turn on

[Bawrice]

For the past few days my PC would run normally but after about 30-45 minutes of running it would reset itself and after the reset neither did the monitor, keyboard or mouse would light up, and now i took apart the PC and when i tried turning it on after disconecting the Graphics Card and RAM and placing them back it will start for about 1 second and turn off and it will keep turning on and off untill i plug it out.
Anyone have any ideas as to what the problem might be? Thank you.

 

[DSzymborski]

Someone might have an idea with a complete list of specs of this PC.

 

[DaleH]

My first guess would be the power supply.