My laptop screen goes white after appearance of horizontal lines on it. This happens after running 2 to 3 hours normally. If I connect to an external screen, the external screen works well. I connect to my LED TV screen through HDMI output. After connecting to TV screen, the laptop screen might start working normally again, up to around half an hour more. But once the total running time of laptop is around 4 hours, the laptop screen will not come back. Thought this is due to heating up of screen, I got it replaced. The new screen is Dell manufacture. But this screen is also behaving similar. What else could be the trouble beside the screen or the new screen is also faulty?
My laptop is Acer 5738. Its original screen got a black spot which expanded and then whole screen became white after few weeks. So got it replaced. The above trouble started with the replaced screen after 3 months of use. For 5 months I utilized my TV to run laptop for more than 3 hours. Three days back I got new screen which is DELL make, but right from first day, I am facing the same trouble. In fact, this new screen is giving trouble after only about 1-1/2 hours.
I would like to mention that rarely (maybe thrice in last 5 months, after I plug in ext screen and am working on it) the computer reboots itself without warning.
What is the problem and how can I fix it?