You seem to be saying that you had a storm outside and your PC blew up.
An ATX power supply CAN stop a surge from destroying a motherboard, but is not guaranteed to. Simply saying it is good because it makes the fans turn isn’t a good test, you’d need to actually take readings with a multimeter.
A multi-rail PSU can be bad, and will still make the fans spin.
If you didn’t have a UPS on the computer and you did hear something pop(PSU kinda boom), the MB is probably dead. You CPU could still be good. Check it in another MB, if you have one with the same socket.
Your RAM is probably good as well.
Although it is possible that voltage came through your Ethernet cable strong enough to fry your MB, your switch, router or modem would be dead then as well. The Corsair PS you have listed is a good supply, but before I’d use it I’d check it out thoroughly. Your transformer could have windings melted and that would throw off you voltages.