I have a Sony Vaio RB40 and the cpu overheated. I turned it off and waited overnight to turn it on. When I plug in the power cord the light on the psu and the mobo blinks and the pc will not power up. If I unplug the 24 pin cable from the mobo then plug in the power cord to the psu the light on the psu stays solid. Do I have a bad mobo? Thanks for any help!