My Compaq Presario came with a power adaptor that claimed it could be used with anything from 110-240 volts.
I used it in the US on 110v for a few years and then took it to China - 220v - after a few months the power adaptor started to crackle and fizz, and eventually it went bang!
The computer wasn’t harmed - there was a surge protector on the line in - but it was pretty annoying all the same. I bought a new adaptor from a guy at the Nova store when I got to Taipei for NT$1800, and it works fine.
(At least, it did work fine. But I’ll never buy another Compaq.)
The computer doesn’t take electricity directly from the wall, it gets a supply from a little black box called an adaptor. The adaptor gets it’s supply from the wall, and should be able to use pretty much anything on offer. You have to have a cable with the right plug fitting to go into the wall, and the other end is a standard plug-in like on a portable stereo.
Check first! There’s a sticker on the adaptor saying something like ‘input 110-220v’ If it just says ‘input 110v’ then you need to get a new adaptor.
Once you have the right plug the adaptor should be able to convert whatever is available to whatever your computer needs. The adaptor connects to your computer using a thin cable with a special plug on the end that may be specific to that computer. Mine had a little thingy on it to protect against sudden surges of electricity during thunderstorms or explosions in the adaptor.
One way to test is to plug your computer into the outlet that powers the air-conditioner in Taiwan. This is usually a 220v outlet, so if your computer explodes you will know that it won’t work in South Africa.
Other things to watch out for:
Operating systems and software might be in Chinese.
You might get hit for import duty when you take it home.
Modems probably work fine, but might not be strictly legal as different countries have different licensing requirements for enything that is to be connected to the phone network.
:shock: While surfing the Compaq site to try and figure out what was wrong with mine I learned that “modems are designed for specific GEOLOGICAL [sic] areas”. Be warned!!