I ' m thinking you may have your LED connectors reversed . Given that you have tested your PSU in another system and it works . For a first build it may be hard to know which way to plug the connectors into the motherboard . It can be confusing . Make sure the power button , power led , hdd led , etc . connectors are plugged in properly on the motherboard . Even with Bad RAM the system will power on and the lights will light . It just won ' t boot . Definitely check your front panel connections on the motherboard . <| sep |> Greek Cypriots refused to settle on Turkish terms . Turkey will in general have to give up the idea that it can conduct comprehensive ethnic cleansing campaigns and then demand the victims to settle with the fait accompli . This is not a viable attitude any more in international politics since the second half of the 20 th century .