Hi guys, I have a big problem with my mac. When I use it, often it turn off. Always when I do different operation. When i had El Capitan in console I saw this message : previous shutdown cause -128. Now I have OS Sierra but in console there isn't a shutdown message when it turns off. I brought my mac to apple store and they test my mac for 5 days. But they told me that there weren't shut down during test. I formatted a lot of time the mac and always he turn off randomly. Someone have the same problem? I know there is another Italian users that have the same problem. Macbook is the same and the seller was the same. My mac is an International version. Please help me, my mac is unusable. Ps: I have bootcamp with w10 but mac turn off only when i use mac os, i don't know why, but it is strange. Mac never shutdown when i was using w10 but when i use mac os sometimes it shutdown a lot of time after the first shut down. thanks guys.