So I just installed a new motherboard, and when I boot up the computer, the computer posts, the boot screen shows up, the computer loads up the CPU, memory, and detects IDE drives. Then the monitor goes black and a little green box with [Hz ?] starts floating on my screen. I can't do anything else. I'm guessing this is an out-of-sync error or something, but how the heck do I fix it? I'm out of ideas.