If you already have a prior version of Windows installed on the computer and you just want a newer version of the OS on the same hardware, you can likely upgrade it for free (obviously this method doesn’t help if you are building a new PC). Upgrade from a Prior Windows Version: Free If you need a product key and don’t have one available already from an existing build or copy, you’ll want to check out method 5, which involves using a low-cost key marketplace. Below, we’ll also show you the different methods for saving money on Windows and compare them.
