Going from 2 to 8 cores made a massive difference to me (although admittedly I also almost doubled single core perf in that switch). Probably for the somewhat o

Going from 2 to 8 cores made a massive difference to me (although admittedly I also almost doubled single core perf in that switch). Probably for the somewhat obvious reason that I usually have far more than 2 programs open at once, so having each program be able to run on a separate core is a huge win. With my previous machine, if I was doing something intensive (like say compiling Xcode), then the performance of other tasks would be noticably slower. On my new machine I can't even tell it's doing it.