why my desktop shut down itself

[joanna]

everytime i use the computer,it will shut down itself and
i didn't even press any shut down button.When the screen
becomes dark, it shows a sentence saying that 'no video
input'. Everytime is like that one and the computer is
not shutting down completely. Can someone help me to
solve it?

 

[Rich Barry]

You might want to check the cable the goes from the Monitor to the back of
the computer. Make sure it's fully connected
and doesn't look cracked or broken. It could also be your Video Card or
Motherboard if you have integrated graphics.