I just purchased an HD 4670 graphics card and attempted to install it in my kid's computer (Dell Optiplex 320)...but I cannot get an image to come up on the monitor to save my life! After initially not getting an image, I did some research and found my PSU was underpowered...so I bought a new one (G-lite 460W PSU). Still nothing. I tested the card to make sure it's working and it is (tested it in my desktop). I cannot figure out why the graphics card is not working! If anyone has any ideas, I would love to hear them.