Originally Posted by hanguolaohu
I'm using a USA Macbook Pro in China and noticed that when I plug in the power which is 220 volts the laptop vibrates. I do not feel this vibration while I use my laptop in the USA which uses 110 volts. I've also had problems with my USA hard drives vibrating and even Final Cut Pro being very unstable while using it in China. I was wondering whether this vibration is normal and whether it could possibly harm my laptop. Any info would be much appreciated!
yes Alexander, I live in Nepal and that's normal but not safe. It means that your power connection is not grounded. Are you using a 3prong plug plugged into a grounded wall socket, or a 3prong plug into a grounded power strip plugged into a 3 prong wall socket? Here is the deal, most chinese power strips sold there (and here) may have 3 prongs but are not wired correctly on the inside. There is no regulatory agency here to enforce proper grounding, hence many devices and power strips are just not. Also possible, if an external drive or external monitor (or any other powered device) is not 3-prong grounded then this will make your aluminum shell seem electrified. If you have 3-wire ground all the way back to the wall, and it's still vibrating, the wall plug may not be grounded properly. Try another plug and another building
The problem that can occur if running this way is that the apple 85w powerbrick can easily blow, and/or the external drive wall wart can blow, and ruin your drive at the same time. I've gone through a half dozen bricks, warts, and drives here already. When working offsite in this part of the world, I always pack an extra powerbrick and try not to use AC powered external drives, but carry USB powered drives instead. In fact, invest in a highly rated surge protected powerstrip and pack that as well. Ha, another tip, whenever I am offsite I insist that a voltage regulator is between me and the wall socket. Our office runs on an inverter system, which has a line conditioner built in, and I have never had a problem even in the wildest of situations. The worst case is working in a building hooked to an emergency generator and having nothing between that and your mac for protection.