Cooling Problem I Think

My friend has an alienware laptop that he thinks is shutting itself down on
high temperture. He got a problem fixed when he spilt a little water on the
keyboard and the touchpad was jumping. He got the problem fixed and it has
been working alright for a week now, p.s. living in shanghai at the minute
and got it fixed locally. Thinks that the fans are not running as fast as
they use to as it is much quieter running now. After say 10mins it will just
shut itself down. He is also having probs getting on the internet hence why
I'm doing this on his behalf.
His laptop is a well spec games machine running XP. Any clues how to check
that the fans are running properly and if not how to fix them. Checked the
obvious and all fans power leads are connected.
Thanks, Marcus.