I would suggest that if you don't want to use your add on, that you go to the device manager (start, control panel, system, hardware, device manager, display adapter) and right click and disable it. Then, shut down take out the card, plug in to the onboard and start up....before you get it booted up, enter the Bios setup menu and set the Onboard card as the one to use in the bios. That should get you going and don't forget to add drivers if you took them out earlier.