Asus HD 6970 wont boot...

Just bought the Asus HD 6970 2 Gb Direct CU II, and installed on my Asus P8P67, but the d.... thing wont boot! 
PSU is a TX 650 Corsair, and when I move the card to another PCI slot (x 4) the PC boots, but of course the performance is louzy...
I

PSU is a TX 650 Corsair, and when I move the card to another PCI slot (x 4) the PC boots, but of course the performance is louzy...
I