Installed 10 and my monitor went nuts

[Michael Novak1]

At around the 75% mark of the WIN 10 install this evening, one of my dual monitors erupted in horizontal rainbow strobe lights. Did a hard reboot with the same result. Did I download the driver for the 4400 released yesterday prior to install? Of course not. Since this is my Admin PC for my business, I need this fixed 3 hours ago. Any and all help/advice would be very much appreciated.