I've got a PowerMac dual 533 digital audio. I've been exploring various upgrade options, including Powerlogix upgrade CPU's, later revisions of the PM G4, and even the PM G5 and Mac Pro. Here is my dilema. This computer is an always on web, music, and video server. It needs to be relatively quiet and cool. That's why I've stayed away from the wind tunnel Quicksilvers. My HD setup also requires I have a case that can fit 3 HD's. That rules out the PM G5. I don't want to spend more than a couple hundred dollars, and don't need the power of the new Mac Pros, so they're ruled out too. That leaves me to sqeeze as much juice out of my dual 533 as possible. If I were to get my hands on a dual 800 Mhz, or dual 1 Ghz chip from a later Quicksilver model, could I plug that safely into my digital audio dual 533? Mactracker lists the CPU in my current computer as either a PowerPC 7410 v1.3, or PowerPC 7450 v2.0. The CPU that came in the dual 800 Mhz Quicksilver is the PowerPC 7450 v2.1. How interchangable are these CPU's?