pw/on is pushed the mb doesnt powerup

New install of a Vc820 mb witm 256mb rdram and a 733 mhz PIII coppermine cpu. The board is a slot one. The cpu is a fc-ppga on an adapter.Which could be the problem. But i would think that the fan would powerup for a second but they dont. the power sup works fine at 3.3v .but when i turn the power on i get nothing. the board has a stand by led on the board that lites up(yellow) when i turn the power on in the back of the tower and stays lit the whole time.so i know the board is getting power.So thats it any help would be appreciated.