Lightening hit by the house and iMac won't boot at all. I've diagnosed it fairly well, I'm down to the power supply or Logic board, but which one? With the diagnostic lights I get the first one meaning I have constant power from the power supply. When I press power button no second light. I've tested the power button and it's working fine. The power supply does make a little noise. I can find a Power Supply and Logic board for $150 online but can it be narrowed down and which should I try first? I'm thinking the Power supply as I can return it if it doesn't work. What do you experts think?