Installing card disables boot menu

when I installed my gtx970 in my gigabyte Ubuntu box, the mouse and keyboard became disabled so I could no longer select the boot options, I just have to wait for it to time out and do its default boot. Ok fine, I thought, then I’ll install the Nvidia driver and it will all be cool, but when I try that, the installer tells me to disable X. When I do that, the screen becomes a bunch of vertical stripes and I can no longer communicate with the PC, so have to reboot to get X back. I tried shutting off X and then moving my video cable to the built-in DVI port, but there was no signal there, so the monitor went to sleep. Is the only solution to remove the card, boot back up, pray it’s not in X window mode, do the Nvidia install, put the card back in, reboot and hope for the best? Seems like there ought to be a way to keep the built in DVI port operational even with the GPU installed. Is there?