You can go all the way to Tiger 10.4.1 on that G4 Alex. k On Jun 22, 2005, at 6:45 AM, Alex Hurst wrote: > Next week I'll be making my first excursion into G4 territory when > I pick up from the UK a tower G4 400 DVD which I recently purchased > on ebay. This apparently can either run Mac OS 9 or Mac OSX 10.2.3, > which suits me fine as I want to ensure that my Classic programs > will still run as before.