Take it from me and up-grade both your RAM, and hard drive space! Video is a space and compute cycle hog. You need as much ram as you can stuff in your machine as well as as much HDD space as you can afford. My workstation is a MAC Pro and has a Terrabyte of ram, and quad processors, and a terrabyte of storage (HDD space). And I am still wanting more speed! I am only editing on FinalCUt Pro HD too, If I was using Avid I would need even more. But, I am at a different level than you as I do this for a living....but you still need a ton of ram and HDD space.