64 bits and RAM are just about making it possible to fit a given scene in memory. By themselves they do nothing for speed. The number of CPU cores is what affects speed. With one or two cores it takes a long time to render anything. With 4 or 8 cores the times are substanstially lower.

When using LuxRender I found that it takes a lot less time to adjust the scene's lighting. So the final balance of time, for me, is actually in favor or LuxRender.

 

Cheers.

Paolo

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