Alienware overheating?

The GTX280M is a rebadged 9800 series chip; it has no similarity to the GT200 desktop series at all. It should perform on par with the 260, but more likely to be slower. (one of them, anyway)

Them overheating is a question of design and how well the notebook is upkept. I'm sure alienware wouldn't sell a notebook that melts down, but they usually don't factor age and dust into their testing.

The better bet is to look at a Clevo notebook. They're not as flashey, but they perform better and have much better designs (and are usually cheaper)