Most likely processor. I gave it to a local repair guy who made me buy a PSU, then a motherboard and finally said that it was the processor. I don't think I was duped since I bought the motherboard and PSU myself. The guy was probably no good and didn't know shit.
After that I moved. The system is still packed. If I remember correctly, the problem was it would not turn on. The motherboard lit green and no display. May be, I'll give a try again this week. Another problem is that the local guy had removed processor from its seating and it was not installed back - I mean thermal compound was not reapplied. Do I risk blowing stuff up without thermal compound?