Automatic powering on and Powering off of laptop issue

did some games download and installed them. I am certainly sure that after that day onwards, my laptop screen goes off and on by itself! As against CRT monitors there is no separate switch to turn on turn off laptop monitors. Some time it flickers and goes off, wait for some time without touching laptop, the screen is back in full shape. What is happening? I have not dropped or damaged my laptop any time. I am sure of it. Even screen doesn’t show any physical damage. Is there way to debug this and find out the root cause? There is no fixed time to turn on back, but by my experience I am sure that laptop screen will turn on again. This repeats endlessly
