iMac 2013 does not want to power up

My iMac works fine recently. I left the iMac keep connected to the power outlet. However, after several surges in the power, I tried to turn on the iMac but it does nothing, no sound or anything. It totally dead and does nothing. I tried to check the power outlet and it works perfectly with all my other device. Tried to do all the resetting advices but it stayed the same.

Any suggestion that I might to consider before I send this computer to technician?

Thanks

Hipo