Zend certified PHP/Magento developer

my computer working but my screen is black

I pulled the monitor wire when I wanted to move my computer, but when I plugged it in again, the monitor showed a black screen when the computer turned on.

I know the monitor is safe because the Lamp of the monitor is on and none of the computer components are burnt because I do not smell burnt and the monitor wire is firmly in place because I have tried it many times. Where do you think my problem is?

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