I just updated my display driver of the nvidia Geforce 9200 GE card on my HP G70-120 EA Laptop. Now after 5 minutes of playtime laptop shutsdown completely. I tried rolling back the driver, but no change. I can't play games like Mirrors Edge which I could play before the problem started.

Could well be a thermal shut down issue.

You need to blow out the vents to make sure your airflow is good.
I had this on my old XPS and a tin of air soon fixed the problem.