So I switch my pc on today and the screen is black. the green light on the bottom right says its on, but there's no display. not even the regular post screen. so i try a different monitor, thinking that that's my problem...same thing. i think maybe it's my graphics card so i remove it and use the onboard instead....same thing. I tried a different cord...nothing. at this point im at a loss. i went through all the other steps......unplugging, clearing cmos, checking connections etc....what else could it be?