cant connect hdmi to projector

hi, i had 2 laptop dell inspiron n5050 and 2 projectors NEC np-v311w

the first laptop projects fine in both projectors

and the second laptop cant connect with hdmi to first projector and when unplugged from first and connect to second projects connects fine, i tried changed hdmi cables with same results, 

second laptop never connect to first projector....

any ideas ???

both laptops had same resolution, same hz, and same driver of video card