Instructions
Turn on your PlayStation 3 Slim.
Select the "Settings" tab on the PlayStation 3's main menu.
Select the "System Settings" icon.
Select "System Information." The amount of free space on your PlayStation 3's hard drive is listed next to the "Free Space:" listing. The number before the slash is the amount of space left and the number after the slash is the amount of total space. For example, 34/160 indicates you have 34 gigabytes free out of 160.