Whether you need a hdd or not depends on your usage, for which no pc knowledge is required. Typically, you wont need more than 100gb for your OS and other softwares. So, you have to make 2 partitions on that drive, as storing data on the Windows drive is never recommended. That leaves you around 400gb for your games and other stuff, which is typically enough for a couple of even big games at the same time. Now if you have the habit of storing all your games along the way like me, then you definitely need a HDD for more storage space. Else, if you play and discard your games and movies, then not much storage is required.