Hey, I currently have a AMD dual core 5000+, and render times are still pretty slow with both cores being used, so I was wondering if I got a quad core would blender be faster at rendering? (Planning to upgrade later this year, not just for blender btw lol)
And, is there anyway to render faster, it takes like a min to render some detailed stuff, slowly rendering one block at a time :S
yes, it will use all four cores when rendering, lest ways it is for me. 
as for rendering faster, I think that there is almost always a way to make something render faster, but it depends greatly on what that is as to how you do that. I don’t know of any fix all methods other then cleaning up everything to the bare minimum of what is needed to get the desired effect. (removing extra faces, lowering the number of particles and so on.)
Are you turning up the thread count when you render? You must do this to use your multi-cores.
To render faster, don’t use any AO, reflection or shadow. You will blaze.
Afaik blender does this automagically now 
If you got to turn down all the features, it sort of misses the point of rendering then doesn’t it.
Heres a tip, delete all your meshes it will render super fast then.
There is a script you can use to drastically lower the poly count of anything you make.
However, it can remove a lot of detail if you aren’t careful. If you play around with it a bit, you’ll see what I mean. If done right, though, you can lose very little to no aesthetic detail, and lower the poly count drastically, thereby also lowering render time, especially when dealing with raytracing.
To access and use this script, select the mesh you want to lower, and tab into edit mode. Open the ‘Scripts’ window (Top window type in the drop down), and click Scripts>Mesh>Poly Reducer.
The ‘Poly Reduce’ factor is the one that changes how much will be removed. Smaller numbers mean lower detail end result. Go too small, and your mesh starts looking worse. The best number here depends on how high poly your model is.
‘Triangulate’ will cause the end result of the script to be in tris, rather than rectangles, though you can easily switch with normal mesh tools.
You should be able to do quite a lot with just that, the other options do a few other things.
This script enabled me to take a katana scene that I had very high poly from around 2.5 hour render time to somewhere around 45 minutes, with AO, reflections, normal mapping, lighting, and so on, with no visible loss of detail in the render.
I got 2xQuads in my machine… renders on all 8 cores in 64 bit Ubuntu. Blender will happily max all 8 to 100% when rendering animations.
Be sure to increase your xparts and yparts so Blender can break up the image into chunks to hand off to each thread.