You did not mention the following in your description, so I'll just check this with you.
The onboard graphics and video card each have separate VGA and HDMI outputs for connection to a monitor, TV, etc. The video card's output is not routed through the video output connections on the mother board. Cables must be connected to the video card itself, or it is not being used.
So my first question is, are your VGA and HDMI cables still connected to the mother board's video outputs, or are they connected to the video card? Or are both of the video sources (onboard and video card) connected to the monitor and TV, with two additional cables?
I can't really proceed until we have this information.
Nothing will be harmed by changing those BIOS options, besides the potential loss of a signal going to your monitor and TV, if things are not connected as I have stated above.
The BIOS can always be reset to its default values, so you can start over again, given you know how to do that.