So I proceeded to find the Aurora screensaver and Flurry screensaver for Windows! Nifty!
But, both of them were getting literally 2-3FPS... Even on minimal settings.. WTF?
Wanna know the GENUINE fix for this issue on downloaded screensavers? Change the file extension from .scr to .sCr - I'm not kidding.. Try it for yourself.
I still hardly believe it myself, but I tried it and it genuinely 100% fixed the problem.. If I rename it back to .scr, it's slow again.. I have NO IDEA why windows does this (especially since its OWN screensavers are lower case .scr...) but it's genuinely a reality!
So there you have it.. Windows can't read its own file extension properly unless you randomly capitalise the 'c', despite the default ones not needing it.. Bizarre.