Need a bit more info my friend. Whats your operating system (what version of windows are you running) to start with. Anything Pre XP i would say its recovering from an error in safe mode.
Either way, a reset should fix it.
Ive had it happen a couple times at work with windows 7. Reset fixed the issue.
Have you changed your monitor or anything recently?
One other way to fix it is to go to control panel and change the screen resolution. Then change it back. This works sometimes.
Try those, if that doesnt work, come back and well try some other stuff.
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