Trouble with nvidia GTX 660 TI Card

I bought a Amd A8-5500 600 Watt power supply and the Gtx 660 Ti The computer currently had a radeon 7470 card in it. With the Nvidia im sitting with a no signal on my monitor. I have everything plugged in correctly i deleted my current display driver and still no avail. Anyone got any experience with this or need anymore info?