The more information you can give the better people can help you with your problem. Which connection on the card are you using to which connection on your monitor? Are the fans going on the card? Do you get a post signal on the motherboard? Is this a new build or an upgraded graphics card?
were you usign the onboard video before the video card upgrade?? if you were see if the onboard video still working. you may have to pull the gpu out to get the onboard video to come back on. makesure the video card in the right slot..closest one to the cpu and make sure the mb has the newest bios.