With Forza 5 and Ryse installed to the hard drive, in addition to a number of other review titles, our concern now is all about storage management. Here's where things get a little strange. As far as we can tell, there is no storage overview to tell you how much hard drive space remains or allow you to delete items in one centralized location. There also appears to be no direct access to save games, either - these and game DVR upload clips appear to be synced with the cloud. It's interesting that in what is the most ambitious console operating system ever produced, the user seems more remote than ever from content.
This would imply that once you reach the capacity limit of the drive (of which you would not be aware), the system will automatically delete older games (based on the order in which they were installed) to make room for the newer games you want to install. LINK