Asus P8Z77-V LX connectors

I have acquired this motherboard but am puzzled as to the connectors - can't get it to fire up

I have a PS which has a 4 pin and 6 pin connector and onboard there is a 8 pin connector EATX12V

I have connected both the 4 pin and 6 pin PS connector to this and shorted the 2 PWR pins together, but no life

If there something I am not doing ??

Cheers