Question no power to my dell 330 desktop

[cmeedesign2]

Hi I have a DELL Optiplex 330. It wont power on no fan nothing but the yellow motherboard light goes on. I tryed replacing the motherboard, front port power button switch assembly, unplugged hard drive and dvd power removed video card and even tested the power supply that works fine as well but still no power. The front power light doesnt even go on. Im out of iptions any ideas whats wrong?

 

[cmeedesign2]

Hi I have a DELL Optiplex 330. It wont power on no fan nothing but the yellow motherboard light goes on. I tryed replacing the motherboard, front port power button switch assembly, unplugged hard drive and dvd power removed video card and even tested the power supply that works fine as well but still no power. The front power light doesnt even go on. Im out of iptions any ideas whats wrong?