XPS M1330 Issues With Projector Attached

I have an XPS M1330. Every time I connect a projector to the laptop, the PC display will remain on for about 5mins before turning off, the same also happens to the projector. I've tried 2 different makes of projector, and the same happens with both. If I plug the same projectors into an Inspiron, both behave as I would expect.

Has anyone else seen similar issues? If so, how do I resolve this please?