There are a couple of key differences between Microsoft’s consoles. The $500 Series X has an optical disc drive while the $300 Series S doesn’t. The Series X is also more powerful. It has extra ram and more powerful graphics processing, which allows it to play games at higher resolutions and faster frame rates. If you have a cutting-edge TV or you want to buy something that’s relatively futureproofed, the Series X is the machine to get.