thanks Mark for your quick answer ! i've try with others aircrafts from P3D and found quite same issue. As i read that v3 as some issues with directx i've finaly choose to change from p3dv3 to P3dv4 which as also lot of improvements.
But...i've still my b737-200 for p3dv3 which doesn't works well so how is it possible to change with b737-300 for p3dV4 ? shal i have to by it or is it possible to have a refund ? Thanks very much !