your monitor is not capable of your current windows desktop resolution, try to boot in safe mode
when the computer starts press F8 you will see the boot menu. use arrow keys and select boot from Safemode once in the windows safemode change your desktop to 800X600 resolution then restart your computer,. you will now see your desktop, now change to 1024x768 or higer and see if your monitor is capable of the desktop resoultion..
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