Octorox said:

Maybe it's not your processor, couldn't your video card have something to do with it? A lot of FX rendering could be video card intensive as well. I'm sure people worked with editing and compositing in HD on normal workstations when quad cores were relatively unheard of.

Its definately not my video card. After effects uses more of the processor and not the card and when you have got around 50 seperate layers & several compositions at a time, each using a different filter then thats where the problem begins. Don't forget i'm not rendering 3D. PLus there is hardly a noticable difference between 720p and 1080p with the HD sources anyway. 1080p isn't future proof either