New motherboard and new CPU but PC won't start

[Silver Bounty]

So I ordered an Amd Phenom II x6 1055t (125 w) CPU and an Asus M5A 78L-M USB3 motherboard and I replaced my old mobo with it but the problem is that when I try to start the PC it won't work. The motherboard shows a green light only. No beeps or anything. No fans working. Nothing, just a green light.

My PSU is 450w so maybe it couldn't handle it but I'm not quite sure about that...

My GPU is an Elsa (Japanese) GTX 750 ti and it used to work perfectly on my previous mobo and processor.

Maybe because my old processor only asked for 95w instead of 125w? idk where the problem is located so I need help ASAP!

 

[Niewierzyc]

have you plugged power switch connector correctly?

 

[Silver Bounty]

yes I plugged it and I made sure it is tight

 

[Silver Bounty]

Bump, hope I get a reply really fast