PC boots but no display on screen?

[Sessenta]

Hi, my computer boots, CPU fan starts spinning, LED on the power button turns on, but there is no video or display on my monitor. I've tried unplugging and re plugging everything but still no display. I'm even connecting my HDMI directly from my motherboard to my monitor. Is my motherboard fried?

 

[geofelt]

Some monitors have multiple input connections that need to be selected via a switch or OSD selection.