PS3 hard drive question

Hey there. So I've been playing my ps3 a lot more recently since my OG 20GB 360 died and I've got a question concerning hard drive space. It's an old school 80GB fat ps3 and I currently have 4 games installed on the hard drive. Bioshock Infinite, Remember Me, Borderlands 2 & Hotline Miami. Those 4 games combined take up a total of 19GB. but yet for some reason when I go to system information and check my hard drive space it says that I have 18GB / 74GB of free space. This would mean that I have used up 56 GB's of space. Besides those games I have nothing (of my knowledge) installed on the system. No photos, no videos, nothing. So.. My question to you folks is: is there and easy place to go and see a list of everything installed on the hard drive like there is on the 360? I've gone through section by section and can't seem to figure out what is taking up the rest of that space. Any help would be appreciated. Thank you

If you go into the games section you can view your saved game files. Maybe you have some files left over from other games or game updates. Shouldn't be taking up that much space but it's a start.

The system software takes up a chunk or space. There is probably a bunch of DLC or patches as well. You can look up those file sizes in the game data utility.

@mosespippy: I was thinking the same but DLC and system updates shouldn't be using 56 GB's. Borderlands is probably the one game that gets patched and has the most DLC. If anything that should be the culprit.

Err, well the HDDS would have the downloaded games, games that you have on disc that download portions of their data onto your HDD, DLC for all the games, saves, and then there is room the system itself it taking up. My guess is there are files on the PS3 that are pre-installs of disc based games that are taking up room you don't know about.