Monitor Problem ? or graphics card ?

[pmw42]

I bought a monitor and I installed it but the screen is stillblack when I turn on my computer, then I reinstalled my other monitor but the same thin happened What could be my problem ?

My graphics card is a nvidia 630

Thank you for giving me as much details as possible because I am 53 years old

 

[prettyflvcko]

Have you tryied to press the power button ? Then your graphics card may not support your monitor resolution....

 

[scout_03]

give up name and model of all parts in the system .

 

[pmw42]

Have you tryied to press the power button ? Then your graphics card may not support your monitor resolution....

I never tought I could forget to press the On button.....

Thank you mister