If you have another computer with a PCIe x16 slot, try it in that one and see if it displays (at least the POST screen anyways.)
If it's not the card, it may be the power. Try removing the power cables from internal peripherals and see if it runs.
If it's not the power supply, your motherboards PCIe x16 slot died. You'll have to get another motherboard.
If it is the card, you'll have to get a new one.