When I first learned to build / setup computers (10 years ago) I was told to partition a C:/ drive for the OS, and to install all games and other files to D:/. Thereby keeping the OS separate from any other files. With my new build PC, I've done that, but what I've found is that modern software, always puts something on C:/ regardless of where the game is installed.

This is very frustrating to me, as now I have a full C:/ despite having plenty of room on D:/

So...is the old wisdom of separating your drives, no longer valid? Should I just have a large C:/ and that's it? Not sure how to avoid programs from spamming by C:/ with random files. PMDG products do this, as well as many others. Thoughts?? I'm a bit frustrated...