ECS P4M900T-M won't boot

Hello, I have just installed a ECS P4M900T-M board and can't get it to boot.
Had to go back to my old system with the motherboard out of the case for a
temp computer until I figure this out. After I got the board in, of course
there is something else that you have to buy. So I went and got a Antec 500w
power supply to work with 24 pins for the board. I am getting nothing on the
screen. Everything is set to default on the board.



I am running a duo core e6300 Intel processor with 2 gigs of Kingston ddr2
667 5300 memory. Everything else is coming right off the board.



Funnything happens when I plug in the aux 12v plug in the middle of the
board, after about 30 seconds, it will shut off the whole system. If I leave
it unplugged it will keep running. So I am thinking that maybe I just a bad
board or a power supply. All the fans and everthing else works, but nothing
on the screen. Anyone have a starting poing that I can start here from?



I have done a few systems so this isn't my first one. But kinda of stumped
here.

thanks,

martinbr