If you just moved everything over from the previous motherboard, there are a few possibilities. For example, there may be a CPU OR memory compatibility issue. The motherboard BIOS may need to be updated.
It worked with my B350 pc mate. Idk y the card won’t work now. I can’t even do a bios update. W/o video
Or it may be as simple as a loose cable connection. Another possibility is that the RAM isn't fully seated. The same applies to the graphics card.
Here are a couple of checklists on this problem.
http://www.tomshardware.com/faq/id-1893016/post-system-boot-video-output-troubleshooting-checklist.html
http://www.tomshardware.com/faq/id-2041564/troubleshoot-boot-display-issue.html