How many processor cores for Premiere Pro/After Effects?

[Fox Hill Photo]

I am looking to purchase a computer for editing video in Premiere Pro and After Effects, and am looking for advice on whether more processor speed or extra processor cores would be more valuable. For example, would a quad-core Intel i7 running at 4.0ghz be superior to a six-core Intel i7 running at 3.4ghz, or would the six-core processor offer better performance?

Thanks!

[moved to hardware forum by mod]

[Fox Hill Photo]

Thanks for your reply! Sorry for the confusion -- yes, by "rendering" I actually mean exporting. I'm looking for a setup that won't require pre-rendering timelines to view basic edits and effects.