Tried it both ways-no joy. Get the message that "Install Failed--The Installer could not validate the contents of the 'BaseSystem' package." on the upgraded 1.4GHz Cube and a can't install on your Mac error message for the stock 450MHz Cube. Someone will have to figure out a hack. Going to try again by installing Leopard on an external FW drive attached to my CPU-upgraded 12" PowerBook G4 (originally 867MHz now 1.4GHz) then booting the Cubes with it. If it boots then I'll clone the external to the internal and try again. Results of the latter to come, stay tuned.... Bill On Oct 27, 2007, at 8:28 AM, Seth Maynard wrote: > Were you upgrading or did you format the hard drive completely? If > you just upgraded, try formating the drive and then installing 10.5. > I hope you had a back-up of your stuff. > On Oct 27, 2007, at 11:13 AM, Bill Fox wrote: > >> FWIW, I could never get any of the later (didn't try early) >> developer releases of 10.5 to even install on my Cube w/stock >> 450MHz CPU or w/1.4GHz PowerLogix CPU upgrade. >> >> I'll be trying the final build (9a581) over the weekend. >> >> Bill >> >> On Oct 26, 2007, at 7:29 PM, Gary Heartsfield wrote: >> >>> Hello all >>> >>> Just tried to install Leopard on my cube with 1.7 powerlogix. >>> >>> All was fine ( 40 mins ) then on restart the cube will begin to >>> load and instantly power off. >>> >>> Now it will not boot from disk 10.5 >>> >>> Just powers off like the shut down was pushed, or pulled the plug. >>> >>> Can start with option key and select the HD and it takes off then >>> 2 seconds later act of the power was pulled in a nice way. ?? >>> >>> Any thoughts ? >>> >>> Thanks