Classic Mac Emulation On macOS, having just resurrected my 2008 Mac Pro from the doldrums, it has now become a permanent feature in the office / retro basement. Giving me the opportunity to play about with some emulation options without disturbing my main work Mac.
High Sierra
High Sierra on a Mac Pro 2008, technically the last officially supported version of macOS for the Early 2008 Mac Pro is El Capitan. However this does appear to be a software cutoff point rather than an issue with the hardware required to run it.