My computer has developed a strange problem, which used to only happen once in a while, but now seems to happen all the time. When I start my machine from cold, the post beep sounds, and the monitor fires up, but all I get is a blank screen. I've sat for ages, thinking it might be installing updates, or something, but I don't think it is, and I end up having to press the reboot button, at which point, I get the 'Windows failed to start...' screen, with the options of Safe Mode, LKGC, etc, and Start Windows Normally highlighted. I wait the 30 seconds, as the USB keyboard isn't 'live' at that point, and Windows fires up perfectly each time. I have no additional drives or hardware connected, and no disc in the CD drive. It's an annoyance, rather than a major issue, but any ideas as to what it might be?