PC COULDN’T turn on by pressing power button!!! After checking Power Supply and ressetting all cable connectors, memory cards, taking out battery from MB and etc… Finally I found solution: I got an idea to try to start power supply as I would if it is not connected to PC – shortcuting green wire (PS ON) with black wire (Ground). Power Supply started and so PC. After shutting down PC (Power supply stay on) I could start it on again by presing Power button. Than I tried to pull out shortcut fom connector while PC is on (with no troubble) and after that I could normally use power button to start and shutdown computer. But I noticed that if PC is not powered on for longer period same problem ocures and after shortcuting green and black wire for a moment I can use power button again normally. I think that there is some problem on Motherboard (MSI) but I coldn’t figure where.