I think there are 2 noises.
When I pushed the start button. After one minute harsh noise start to come but screen is blank.
After some time may be 2 -5 minutes later harsh noise goes away and small noise stays. But while doing nothing every once in a while harsh noise comes and goes away minute or two later.
I don't know if this harsh noise is hard drive spinning and small noise is fan moving or vice versa.
Q. Can I use my mac notebook screen as a moniter to my troubled HP notebook to check if notebook itself is ok? If yes what kind of connection I should look at?