What video connection are you using: HDMI or VGA?
What's the resolution and refresh rate of the computer's video output?
Some home entertainment devices (usually receivers, possibly some TVs) do not support the large variety of resolutions that computers can. Only "standard" entertainment resolutions work. e.g. 1080p (1920x1080 @60fps), 720p (1280x720), 480p (640x480. 854x480), etc. You might need to explicitly set the netbook's output video resolution to one of those.