Hi all, I just wanted to share my recent upgrade experience with you since the question of what impacts Zbrush performance most arises here quite often.
We all know Ram is crucial and that the GFX card has practically no impact.
So what about the processor?
Just a few days ago I finally decided to kick out my old 4 years old Core Duo CPU and get a new motherboard with a state of the art processor, - a i7-950 Quadcore to be precise. I also upgraded from 8 to 12 gb of ram, just to be on the safe side 
now let me tell yo this - the impact on Zbrush from this upgrade was massive to say the least. a sculpt at subdivision level 7 where I usually add all the details like pores and fine wrinkles let me scratch, cut and carve through it like butter at any speed my hand is capable of, where before I had noticeable lag and most of all, dotted lines when I went to fast.
no more dotted lines and full viewport rotation and zooming speed without any lag.
so, if you are asking yourself if a cpu upgrade would be worth it, the answer is a definite yes.
on a sidenote, I took the risk and tested if windows 7 (64bit) can digest a chipset/motherboard swap without the need to reinstall the OS from scratch. yes it can. I powered down my comp, unplugged, exchanged all the hardware, turnded the comp on again and windows took roughly 10 - 15 minutes and 2 restarts and I was up and running again as if nothing happened.
cheers
J.
