Thank you both, cleared it up perfectly. I accidentally typed After Effects about the cuda/mpe feature. What I meant to say for the bonus question was about Premiere Pro. Does what I mentioned apply to Premiere Pro? It would be nice if both the standard/spacebar and 0/keypad previews were rendered with the help of mpe in Premiere.
By the way, one more thing and I’ll have this down perfectly: when you say that the spacebar also uses cached frames, is the cache actually put into your ram, or is cache more like something Premiere temporarily stores on your hard drive?