thanks for the reply... i am new in mac's world but i realized that kernel panic is similar at the blue screen of windows..isn't it?so i'm trying to understand a reason why i recive this "blue screen" and i have a trouble: does leopard support ddr3 ram? i think that it supports it... do you know if there are direct links to the 2 distros that you have suggested me? i know that google is a powerful "weapon" but i don't know which version of them i have to search