Maybe, maybe not. And no, you will never see a "frequency" switch.
The first thing I would do is look at the nameplate and the instruction book. Computers are made for the world market and many will auto switch or have a voltage selector switch. If this is the case the different line frequencies will not matter either.
If you really want to be sure otherwise I would contact the manufacturer. Switching power supplies could have problems with different line frequencies unless they are designed for it.
-Hal
