i am trying to install mac osx on to my mac, but the problem is the dvd dive broke a long time ago. so i dint bother to go to apple store to get a official osx disk, i downloaded the "osx-leopard105.iso" 7.5gb and restore it on to a 8gb flash drive, i restart my computer holding alt to boot of the usb. it got in to the installing screen and the first page ask me to pick my language, i picked and press next this error msg pops up "mac os x cannot be installed on this computer" i try partition 20 gb out of my hardrive and try restoring the iso off of that and booting it but same thing happen. can anyone please help me?