Color Grading Cluster help!

Hi all.

Is there anyone here who can help me set up two G5 Dual 2Ghz Powermacs in a cluster to do intensive color grading work? They will be liked using "Small tree" software. http://www.small-tree.com/mp_cards.htm

I was hoping for some feedback from members who have done this before, and was also interested to know if the speed at which I can do the grading will be limited by CPU or Memory. Will putting ********s (8GB) of Ram into each machine make a big difference or will it be limited by the CPU?

Any help is greatly appreciated: I am on a bit of a tight leash time-wise.

Thanks all.

~Ozi.

EDIT: Also, what software is used to run the cluster? Does one powermac control the other? Im wondering because Virginia Tech i think had custom software made to run their nodes. How would it work for this little cluster I am looking at making?

(Sorry for so many questions... I am totally new to this entire thing. )

EDIT 2: If anyone has experience with using an Apple computer to make a cluster, how did you do it? Any advice would be great. Thanks.