No, the only way it would "break" is if it overheated to the point of melting causing serious damage. You can do it, it's easy especially with powerstrip, just small increments.
...and no, just increase the speed in small increments, and then start playing a game or something, and boost up the resolution and stuff, if it is too much, your computer will be unstable...
no prob... just quit the game, change it back a little, and restart...
there you go!!