Laptop shuts down...Overheating?

Everytime I use my laptop for more than an hour or so the
screen starts to get all of these vertical lines and will
sometimes shut down. I am usually multi-tasking (running
media player, outlook express, excel, etc.) I suspect
that the system is overheating, as the laptop is pretty
darn hot when this happens. However, I am not sure if
this is the problem and just wanted to see if anyone else
has had similar problems.

I have a sony vaio pcg-grx560. I could not find any help
through sony.


Thanks,
Brent

Laptop shuts down...Overheating?