Well, naturally a quad-core CPU could be much faster then a dual core, so if ur looking for pure render speed, i'd stick around and wait for the quadcores and see waht kind of increase in speed they deliver and if bryce 6 works with 4 or more cores.

Also another important factor could be ur budget, as brand new quad cores probably wont come cheap.

Just for a little comparison on multi-core performance inpact; A scene which my Inspiron Laptop with 3Ghz P4 with HT rendered in 46 minutes was rendered in only 19 minutes on an Alienware Laptop with an AMD Athlon64 X2 3800+ (which is a dual core cpu). The Alienware also had twice as much RAM (2gb instead of 1gb) but the scene wasnt that memory-heavy so i dont think that made much difference.

So basically the newer dual-core cpu's can perform around 2 times faster then the HT single-core cpu's. Multiple cores are defenitely a blessing for calculating performance (provided your program utilizes multiple cores).

I've also been told that Opterons are faster then Xeons. and the 270 opteron is already very significantly faster then the 248 (i've heard figures claiming its 40% faster or more), so be aware that the changes in numbers can decieve for these opterons, looking at benchmarks is very much more helpfull.

Also, make sure your powersupply is sufficient. These fast render systems are absolute power-hungry monsters. Latest system we built over at my studio has a 900w powersupply..

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