i will tell u this now, AMD or Intel, doesnt matter, when you render, your still going to be waiting forever for it to render. you might aswell save some money
i personally dont feel any difference moving from my old phenom II to core i7 (both nehalem and sandy bridge) when it comes to 3d applications.sure intel may be faster, but its doesnt feel that much faster. i would be more worried about things like ram and graphics cards at this point 
just my 2 cents
EDIT: i would also worry about motherboard more, when i was using an asus rampage III extreme, in 3ds max, when i tried using reactor 3ds max became unstable easily. i replaced it with an MSI Big Bang X-Power and was able to use reactor, and 3ds max in general with much much more stability.
Last edited by nfsc; 08-13-2011 at 07:38 PM.
Regards,
NFSC
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I am currently working on a lot of secretive projects for animation sequences for videos me and my friend are making 
CPU Core i7 930 @4.2GHz
Memory 6GB Corsair Dominator 1600MHz
Graphics Card EVGA Nvidia GeFroce GTX480
OS Windows 7 Ultimate x64