The first one mean literally

You have no interest to die

The second one mean

Your interest is to not die

The difference is subtil, but the first one sounds more like a threat/warning, the second one sound more like an advice, even if both mean the same thing.

I would say the first one is unlikely to be used literally as it somewhat implies that to be killed is no big deal. Something like:

I would not recommend for you to be killed.

or

You wouldn’t take advantage of being killed.

This might be used in a game where you have multiple lives.

The second one is more a warning/threat:

Make sure you don’t get killed !

Avoir intérêt à signifie littéralement qu’un gain est à attendre de l’action énoncée ensuite.

• Tu as intérêt à ne pas faire signifie donc que tu vas gagner quelque chose en ne faisant pas.

• Tu n’as pas intérêt à faire signifie qu’en faisant, aucun gain n’est à attendre.

Donc, selon l’expression, l’espérance de gain est subtilement différente.

Tu n’as pas intérêt à X.

Means you would gain nothing from X, but it doesn’t imply that X would hurt you. However,

Tu as intérêt à ne pas X.

Implies that X would hurt you and you should avoid it.