Acer Aspire Laptop keyboard problem .

This member of my flock has an Acer Aspire laptop.

It gets very light use - Surfing and E-mail [Hotmail account] all of which works very well all the time.

However when the user uses the Acer Aspire Keyboard for composing E-mail or a Document the machine will shut down after a minute or so of typing.

As the user is a 'Pick'n'Poke typist I wondered if by some chance he tapped or brushed over a function key.

So I sat and watched him - Nothing there =he carefully selected the keys to tap but eventually withig a minute or so the machine shut down.

Any thoughts please.