Power supply could not have enough power to run the card, card could be bad. Test it in another system. Make sure your power supply is OK to run the card. May want to do a BIOS update on the system, then try installing the card again after you checked the first two.
My power supply is good enough. I ran this card in another system, with 30 less watt on my psu, and it all ran fine. So I think it's not my PSU / A bad card. I could try to update the BIOS. I will try that later.
I want to buy a new video card (Sapphire HD 7770 Ghz OC), but if this one doesn't work I don't think my new one would.