1 - 2 horas
Nothing happened when the power button was pushed. I have seen this before and knew it was a failed Power Supply.
Repair went well using the ifixit guide for the replacement of the power supply. Pushed the power button and voila!
I have an ifixit tool kit which is tops. The screwdriver head is a little broad for getting in to remove the LCD retaining screws. Fortunately the imac plastic case has enough flex to widen the space with a wedge to allow the driver access to the screws. Don't be shy about wedging it unless you are sumo prone it won't break.