While Apple lists 867MHz as the minimum CPU speed for running Leopard, this of course is a subjective judgment on what responsiveness is acceptable to the user. The 700Mhz iMac ("Luxo") falls below this cutoff. So, 1) does Leopard allow itself to be installed on such machines, or does it seize control from the user? 2) Has anyone tried installing Leopard on a sub 800MHz mac? If it is up an running, how is the usability?