tl;dr don't, just don't.

A curious little me (12-14 years) just stated using the family shared computer.
And he thought: It's so slow! Maybe I can make it faster, my parents would be happy!

So he looked at this little switch on the back and he switched it from 230 to 115.

Not knowing what he did, he turned the PC on... for the last time.

Smoke, a nasty smell and a loud bang were the last memories left behind.

The parents were not happy.