I'm having problems with one of my old PCs. I recently did a clean install of XP, but when I booted it up, all I saw was the POST, then the Windows loading screen, and then a black screen without anything on it. So I rebooted again, and I got the disk check, then the black screen again. I rebooted several times just to make sure, and somehow the POST and loading screen stopped showing up, so all I saw was a black screen. Also, during the black screen the LED on my monitor keeps blinking amber, then green, then amber, and so on. What's going on?