Is it safe to use a power supply with a different laptop? [duplicate]
Turn it over and look for the voltage and amp rating. If these are the same, then it is 100% safe and guaranteed to work. You can use alternates when it is different, but it is not always safe just because it fits.
You want to look for something like this on both devices:
Input to the power adapter is not to important, you want to match up the output of the adapter to the input of your laptop.
Current Dell adapters are 19.5 volts (including all of the Vostro lines that I've run into.) So do not plug in that Sony adapter.