Coming back to this, I'm just curious if anybody has any idea how much of a performance impact the presence of L3 cache has on a G4. I ask because I was reading about upgrade options for the MDD Macs, and it seems that of the three third-party accelerators listed there, only the slowest (dual 1.33GHz) has an L3 cache. I've heard some anecdotal evidence that it can make a noticeable difference, and given that the main bottleneck on fast G4s is the FSB (167MHz and no DDR support, IIRC,) I'd imagine that it does, but I'm just curious if anybody's made thorough measurements. If it is a real performance impact, I'd kind of suspect that swapping in the dual 1.42GHz CPU card (with L3 cache) from a FW800 MDD would be the best option all-around, not just for OSX...