Memory questions

I have a laptop with 4gb of memory. "Psychonauts" works well, "Ratchet and Clank," not so much. Obviously, the problem is that there's too much moving on the screen at the same time. My question is, would increasing memory to 8gb solve this problem, or is it a problem with the actual processor? Memory, I MIGHT be able to do something about... processor, I'll just have to do without.

Thanks.

""Forever a n00b!""