I have been instructed to purchase a Macintosh computer for my workplace that will enable us to do video-conferencing. I am an experienced Mac user, although I must admit that my knowledge of PPC-based systems is below average -- I only got my PowerMac 7200/75 eight months ago, and that is hardly top of the line. I have never done any video-conferencing, so I don't know what the system requirements are for this (I assume they are above a 7200/75).
What are the most important things to consider? Speed? Is 180 MHz enough? Chip? Will the 604e give a much smoother video-conference than the 604? How much VRAM or level2 cache is recommended? I will be extending the capabilities by adding the camera and such -- will I need a few extra PCI slots too?
I would prefer that you answer from experience, either first hand or second hand. I am smart enough to guess that the most powerful, fastest machine will give the best video-conferencing -- but can I get away with something less expensive?