I have found solution, the problem is so small and funny, unbelievable small. I had problem few days, totally black screen and only three beeps in intervals, no boot. And i don't wanna to give a lot of money for nothing so i decided to do everything which i know and to fix it or trow it in a garbage. I have tried thermal paste, have checked the memory chips on logic board, soldered the new one, but again the same. The problem was that thermal sensor which is on the small board and glued to the logicboard (i don't know why they do like that) have take apart from it and touching the metal part of cooler and making a short circuit. I had glued back again, put the paste and cooler and, woala, air is on the air again hehe the location i have marked on picture with red. the location of thermal sensor hope you will find this useful. Greetings from Serbia Zdravko