at was a 2i ame lifing off a very tight budgret and got mesed o ve whin i got my firest mack the outher day i bout a power mack prow that5 is a 2008 he tried to put in lion 10.7.5 and did not tell me k now im told i half t5po figer out how to reoinstal the lepard 10'5 in it and i9t will not take the optichion keys tat everyonjhe says use a teck told me it was to old for most of them how can i make it b oot to a usb flash drive