Network Controler Driver Needed

I have a dell dimension 3000. The network controler driver is listed as not being installed. I called dell and they told me what driver to download, r78727. That driver downloaded and the yellow question mark is still listed under network controler tab. I tried to install the driver maually by having the computer use the r78727 driverpath and the program will not except that. I'm at a loss of what to do. Any help would be excepted.

Eric