All you have to do is add up the games that your installing to see what the total is and since 1gb = 1000mb I will say that yes all the games will fit. The system requirements on the side of the box should give you the hard drive space needed for one game. Let's just say for example that one game uses 10gb of space and that there are 10 games in the Total War Collection, then the space needed is 100gb and that leave 400gb free. Using another 100gb for Windows and various applications and that still leaves 300gb free. So for now you can use the 500gb and mean while save up for another hard drive and add that later for more space.