jeffmint wrote:Mode not supported
This simply means your monitor doesn't support the resolution or refresh that is being sent to it. Try adjusting the settings in the nvidia-settings applet. If all else fails, just de-activate the nvidia driver in Additional Drivers and restart, it should revert back to the open source driver as after installation. There is usually more than one nvidia driver in the list, sometimes you need to try a different version, read the descriptions of which version supports what cards to match to yours.