The caveat is that you have to trade in your computer at a Microsoft Store, and you have to buy a new Windows 8.1 machine that costs $599 USD or more (limiting the maximum discount is roughly 16 percent).Source: DailyTech
The good news is that most of the laptops and desktops at Microsoft stores are relatively new, so it's unlikely that Amazon.com, Inc. (AMZN), Newegg, and other online retailers will be able to offer a better deal, on average.
Microsoft to give you $100 for upgrading from XP to a Windows 8 PC
Posted on Monday, March 24 2014 @ 12:05 CET by Thomas De Maesschalck