After two consecutives power outage, my XPS 8940 cannot turn on

In my area, it's pretty common for small power outages to happen some days, especially when they're constructing a building, but today, after two power outages, my PC can't turn on anymore.

When I plug the power cord into the computer, a dim light comes on and goes off in 3 seconds. Then I try to turn on my computer, but I have no answer.

I opened it, checked if everything was ok, unplugged some cables and put them back, but nothing happened.

Does anyone know what this is or can I only solve it by going to a tech support?