Well, Windows take up some space but not that much. to be clear, what programs did you install?
Photoshop as well as a few (6 or so) games, so far, among a bunch of miscellaneous programs. It may be worth it to note that there are a few modifications on some of the games which read as the size of the game file in the Programs and Features menu, causing them to be calculated multiple times when in reality they are only small. As far as I know this is because the Programs menu calculates the program size based on the directory, so if a small program is installed within a larger ones folder, it will be calculated twice. This causes the Programs menu to display the total size as 140GB, even though I know that's not correct.
Could this be the issue? A misreading of disc space?