I agree pull everything off board leave it in case
only hook up
power switch plug , power supply , video card, and 1 stick of ram
you don't need anything else to boot t bio,s
Oh wait here could e your problem
You say a new board how about cpu is it new and has your board been Bio,s updated to handle such cpu
I bought a new board and then new cpu and it would do just like yours is
come to find out the board had to be flashed to use the cpu I chose so I installed the smaller cpu flashed bio,s then reinstalled new cpu
worked like a charm
goto board web site and see if bio,s update available and see what it fixes
Hope this helps