How do I stop using so much memory

Hello! Recently, I’ve noticed my fps being capped at 60 despite being allowed to cross the threshold of 240, something that it usually runs at. I believe it’s because my memory is running at a 2900MB in game. I tried to turn down my graphics but that didn’t change a thing. I’ve been trying to fix this problem for 3 hours, any ideas?

Image of the problem.

Is it a constant value of 60 or does it vary a bit?

There’s a good chance that there’s something else at play that is limited the FPS, rather than the memory (2.9GB isn’t that much)