Choosing the correct laptop adapter is all a matter of voltage, output power, and proper connection. If all of these things do not match the original specifications of your computer, than a new laptop adapter will likely not work on your machine and may potentially cause a lot of damage. In the end, most replacement adapters will have a list of computers they are compatible with.

The first thing to consider for the laptop adapter is the voltage. The easiest way to check this is to turn the computer over and see if there is a voltage listed anywhere on the bottom of the machine. A sticker may be affixed with this information and other similar laptop specs listed. It should be a number with a V attached to it, such as 19.5V. This information is also available on the original adapter, if it is available.