Clear RAM without rebooting article

I saw another article with a similar method as yours, but it required a second vbs file to be run. What's the difference in the two?

I'm also confused that your example is for 24 MB, rather than something in the GB range? Is that the maximum recommended to clear at once using this method?

Right now Windows is storing about 15 GB that is otherwise unaccounted for, which I'd like to free