GFX card and onboard chip

I have a nForce 220D Motherboard with a onboard GeForce2 which runs guild wars but at a less than desirable performance. It is a AGP motherboard and on that AGP slot is a GeForce 6600GT 256mb.

My problem is I was having some boot issues and fixed the problem after taking out my RAM and putting it back on its slot. While I was troubleshooting I unplugged everything just to make sure it was not any of the other devices causing the problem. One of the devices was my AGP graphics card.

After booting I realized my video connection to my 6600 but it has no signal. So I plug the video to the botherboards onboard GPU and it works.

I uninstall the nForce Drivers and the Forceware drivers. Then go to install the Forceware drivers but it does not detect my onboard AGP card. The card is plugged in and works the fan spins and everything. But the computer does not detect it and the onboard GeForce2 drivers are installed instead.

My question is how do I install the drivers so that it detects my onboard AGP GeForce 6600GT?
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I fixed the detection process it was a power issue... after replugging the power the detection seems to work fine... there have been some known issues with nForce motherboards and GForce 6xxx series

you are confusing :O - you talk about an onboard Geforce 2, THEN you mention "Onboard AGP GeForce 6600GT" --

You would have to disable/enable as you wish in the bios, and to not use the card in the AGP Slot (which ever it is) you would have to physically remove the card in the AGP slot

98% of the time, removing a video card and rebooting will turn the on-board on automatically.

It sounds like your video card may have died.