Aspire Z3-600 screen keeps cutting on and off when watching/streaming videos.

I have a 2015 model Z3-600, and have had the same problem for quite a while. I originally bought the computer for my wife, who was very near blind, and rarely used it to watch any videos. When it was new, there were no problems with it, but as it aged, she would complain about the "flickering" you are talking about. As her sight worsened, I would cast her screen to a larger monitor so she could see it, so the "flicker" didn't matter. But, that told me it was a monitor problem, not elsewhere. When she passed in November of 2017, I packed her belongings and didn't much think of it again. My own PC went down last month, so I had to unpack hers (now mine) while mine was being repaired. It did the same "flickering" with me. I moved it to my bedroom to, basically, use as a radio( sound was great), but I got to where I couldn't stand it knowing it wasn't "right". I was going to take in in for repairs until I lost my sleep mask. I adjusted the brightness (which was as high as it could go because of the wife's near blindness) to a much dimmer level so the light wouldn't bother me while I slept. When I woke up the next morning I accidentally clicked on a video file, and it played perfectly. No flicker at all. I tried YouTube. it was fine. I imported moves from an external hard drive. They played great. I have been testing the upper limits of the brightness control, and have gotten up to 75% with no problems, but I could use it even dimmer than that, if need be. I think maybe Acer designed a super bright screen without realizing that their video processor couldn't handle it.......just my experience.