Try using auto-detect,
http://www.nvidia.com/download/scan.aspx?lang=en-us
I tried this already, and I still can't download the driver, the install runs for hours but never finishes up, I'm trying to put it in an old HP Microtower dx2300 desktop, the card fits into the pci-e slot just fine, and when I hook up the monitor to the HDMI, it doesn't acknowledge the card is there, keeps telling me to hook it up to DVI/HDMI port, and how do I disable the onboard gpu on the motherboard, do I use, Device manager.