Can't get any display in Live TV mode or window on menus or in config.

[wn01]

I am running Sage 6.3 on a Dell Precision desktop with a Hauppauge 1600 HVR card and a Nvidia Geforce 5200 display adapter. Sage ran fine for 2 weeks. Then the audio stopped working. I reinstalled the software, got on this forum and tried a new audio setting someone suggested and it worked. Then the video stopped playing in Live tV mode or on the menus, this happened a few separate times. Each time I did a clean install erasing the Sage program folder each time. Nothing worked. Finally, this past weekend I spent the better part of a day reformatting my entire hard drive, reinstalling all my software, including Sage, and, still, sage will record but the video won't play on my tv or monitor in watch live tv format or in the menus the way it used to. Nor can I get video to play using any of the settings in the video source configuration

Any suggestion? Thanks.