[Brian Charles] "After Effects can use 3GB per core."
Just a point of pedantry -- Ae can use far more than 3GB per core. The 3GB per core figure in the multiprocessing preferences is the largest default minimum amount of RAM you can require Ae to allocate for itself, but if Ae needs more RAM and if more RAM is available, it can use it.
Of course, Brian and Ted give great advice (as always). The only thing I'd add is that some comps are more CPU-intensive, and others are more RAM-intensive; it's not universally true that it's better to have more cores running with less RAM available to them. Sometimes fewer cores running with more RAM each will render faster.
Walter Soyka
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