Right now I have a stock Feb 08 mac pro, aside from 2GB of after-market RAM: -2x 2.8Ghz Penryn XEON -4x 1GB RAM for a total of 4GB (soon to be doubled) -1x WD 320GB SATA Hard Drive Right now, I perform the following tasks on it: -Java/C++ Programming/DWeaver Web development/minor image editing -Lots of Video Encoding -1 or 2 VMware VMs running full time: Windows XP32 with Java or MS IDE running Red Hat AS with Apache Tomcat and MySQL running I've already decided to double the RAM for the sake of the VMs. What I want to know is how much striping and mirroring 4 drives might help me. If it will, which of the above tasks would noticeably benefit? I don't know much about RAID, aside from the benefit of mirroring drives. The machine is running well now, but if there is better performance to be had, short of upgrading the CPUs, I'll take it. Thanks in advance. P.S. Would you recommend even more RAM? If so, what would be your minimum.