i did the most common things that is change the power cable .. changed my psu . changed my cpu cabinet and apply heats sing paste too....and also change my os from windows 8 to windows 7 ultimate ,.... but still having the prob.... the time my pc shuts off ..the very next try to "on" of the pc is being failure .... only the fans are running for some time and than it shuts off again.... than after only m able to switch on my pc.....pc having amd fx 6300 ,gigabyte 970a mother board, asus gt 610 2gb graphics card and 6gb ram