Technically you cannot upgrade to 10.5 because your CPU is slower than 800Mhz. However many of the G4 upgrades from OWC should work proper with 10.5. If you feel the need to spend the Cash to upgrade your Trusty G4 then do so. But bear in mind, no matter how many dollars you spend on a New CPU just to run a Faster OS, your computer will still be slow due to other factors: System Bus, RAM, HD controllers. Sorry, Luke Rademacher Liquid Zone Graphics Mac mini 2.0Ghz Intel Core 2 Duo, 3GB RAM, 80GB HD, Combo DVD/CDRW, Mac OSX Leopard 10.5.5, ext NewerTech miniStack w/ 320GB HD. MDD Dual 1.25Ghz G4, 2GB RAM, 250GB/120GB/80GB HD's, 16x DL DVD±R/RW Superdrive, Mac OSX Tiger 10.4.11, Classic Mac OS 9.2.2. External 1TB HD FireWire 400 Intel Celeron 2GHz, 1GB RAM, 80GB HD, Ubuntu Linux 8.04 5.5th gen 80GB Enhanced Video iPod Canon CanoScan 8400F Canon Pixma iP4500 On Jan 5, 2009, at 5:03 PM, c m wrote: > I have a PPC G4 sawtooth and I have been contemplating upgrading to > 10.5 > > my current specs are: > > 400MHz cpu > 2 hard drives: > 120G HD > 10G HD > 1.5G of RAM > > will it benifit me to purchase this:http://eshop.macsales.com/item/ > Other%20World%20Computing/MEG42M1200/ as 400MHz is awfully slow? > > > > > >