Start with the a static discharge and work from there . Unplug the computer and hold the power button down for 60 seconds. then plug in the computer and try it .If this brings no joy try removing the ram and trying it with 1 stick at a time .there could be a bad dimm and one will keep the computer from running . If your board is equipped with a mem refresh button now would be a good time to push that. If no joy is near now try replacing the power supply . If you still have no joy then you may need to look at the motherboard or processor. Hope this helps keep us posted