My iMac Intel 24" had a problem where when the power button was pressed, the light came on, and the optical drive spun up and that was it. No chime, beeps, nothing. But the computer seemed to be on. I took it to Apple, and they said bad logic board, so I bought a replacement board online and did the repair. Fired it up, exact same issue. Could it be power supply? It looked fine, no bad caps, and it is receiving power, maybe not all power but some. I took out the ram sticks for the heck of it, and the power light did 3 flashes, so it sees changes. I really doubt I have two DOA logic boards. Any ideas? Thanks!