Long story short, I've come into possesion of a hand-me-down mac. It came in the shiny silver case with the apple on the side. Threw some ram and a harddrive in and installed OSX thinking it was a G4. The system info says it's a G3 300mhz. I assume that they must have put an older model mobo/cpu in the newer case. I want to upgrade the processor, but having no experience with macs I'm not sure what I'm looking at. All the upgrade and mac info sites I've been to identify mac models by case color, which obviously doesn't apply. The motherboard does not appear to have an agp slot (unless mac agp's are pin incompatible with pci agp's), it does have a slot shorter than the pci slots, but the same color. It has 4xDIMM w/ a 100mhz FSB and, as mentioned, a G3 300mhz proc. More to the point. Can I bet on any G3 processor working? It seems that you can upgrade G3's with a G4 processor. Can I bet on any G4 processor working? If not, what specific info is needed to identify my mac and where can I find it? e.g. location on motherboard, case, specific directions on where in OS. I'm a true mac newb so directions like: Click apple icon in top left corner of taskbar, choose x, go to y, etc. are needed. Thanks in advance.