The minimum requirements for Zimbra are a 1ghz CPU.
What about installing in a multi-processor environment? I've been watching ebay and I can find a mutli-proc server rather cheap. One I'm looking at now is a 4x500mhz system. I'm rather new to linux and Zimbra, so how would linux / zimbra react on a server such as this? Would it meet the minimum requirements? And what would I need to know about installing in a multi-processor configuration?