|Your info is confusing and some of it is WRONG. |
In the Motherboard Specifications, M2N68-LA (Narra):
Your CHIPSET is Nvidia GeForce 6150SE, nForce 430.
It has integrated graphics - GeForce 6150SE .
You cannot physically remove either of them!
" NOTE: *Either integrated graphics or the PCI Express x16 slot are usable at one time; they are not usable concurrently."
Aswith most mboards, the onboard video is automatically disabled when you install your new or any video card in the PCI-E X16 slot. The video port on the mboard will NOT produce any video when the card is installed!
"The VGA cable is the only one I have for my monitor and it connects directly to my mobo."
"Will the new graphics card not work if I don't plug a DVI-I cable directly to the card?"
The card may be working fine, but you'll get no video unless you connect the monitor to it!
You MUST connect the monitor to the new video card. Most video cards with one or more DVI ports come with at least one DVI to VGA adapter that plugs into a DVI port. You plug the VGA cable into the VGA port on that adapter.
Did you look for that in the box it came in?
If the video card did not come with a DVI to VGA adapter, buy one !
The new video card may require an additional power connector from the power supply to be plugged into a socket on the card. If so, did you plug that in? If so, the video will probably not work without that.
You DO NOT set the Primary Video in the bios to Onboard when you have a PCI-E card in the slot - the video will still work in Windows, but the video will NOT have the enhanced capabilities the specific drivers that will be loaded for the video chipset in Windows support. That should be set to PCI-E.
One port on the video card is Primary, the other is Secondary. Sometimes a single monitor must be installed on the Primary port in order for the video to work properly. See the instructionsf or the card if it has them, or look for labelling on the card.