My older MACBOOK works great with one problem. I get serious "breakup" of the screen unless I gently support / pull the upper left corner of the screen/case toward me. It seems that a very sight twist of the screen solves the problem but then I have to work one handed. It also works well if the upper left corner is propped againsts an object. Symptoms include: horizontal lines across the image, white-out & fade-out. During those times the cursor movement, or any animation, stops until the gentle tug on the upper left corner restore the image. Can it be the flexible cable from mother board to screen is crimped or...Is my MACBOOK en route to being pooched? 
