Jim, You are correct in assuming that the Intel chip is not required. As far as your G4 tower, it depends on the processor speed. According to Apple's "Tech Specs" page for Leopard, you need a G4 at 867mhz or faster http://www.apple.com/macosx/techspecs/ You would be wise in checking if your Macs meet the minimum hard drive space and RAM requirements though, before attempting an upgrade. Hope this helps, lc_Chris ----------------------------------------------------------- MUGLO information at <http://www.freewebs.com/muglo> Manage list subscription options at <//www.freelists.org/list/muglo> -----------------------------------------------------------