projector cutting off the top of my screen

I have a latitude 6520 and when i connect via hdmi to my projector the top 5% of my screen is cut off. When i connect via VGA cable this does not happen but cannot project 1080p. I have tried to change the settings on my HD projector but no help. Can someone help me? 

Also, i have a studio XPS laptop that when i connect to the projector via hdmi i do not get this issue.