My mother's iMac found its way off the desk and onto the floor with a sweet crash. Since it wouldn't show any sign of receiving power when turning it on, I decided to take it apart thinking that the power supply was shot. It definitely was shot. There was a black burn mark and weird spidering visible on the power supply's circuit board. (see attached image)
It went great. The video easily walked me through the process.
Always make sure to take off any rings before working with power supply components.
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