Greetings from Ecuador! Here I am, hundreds of miles from home, and my Mac is dead. Sometimes, it starts up, but the screen never comes on. And if the screen does come on, the display freaks, freezing the computer and producing these weird lines on the screen. Can anyone verify that this a problem with the logic board? Based on my serial number, I may be eligible for a free replacement. But I opened the case once, so they might not like that.