Asus all-in-one display goes to colored vertical lines

I have a 27 inch all in one Asus, just one year old. A few months ago when it would go into sleep mode, the display would go to colored vertical lines. I would reboot and the computer would restart normally. Annoying, but not a big deal. We turned off the energy saver mode, so that we would avoid the problem. Now, however, at night sometime between 12am and 6am the computer switches over to...