Chosen Solution
The screen has an overall flicker of vertical bands, some purple, some yellow 3/4" wide, and some 2" wide. updated with most recent software Also tried to reset NVRAM ( option+command+p+r ) but nothing happened ??
Not good! This likely a bad display. Connect an external display if that looks OK that proves it! Now we could offer more but we really need to know which model. If you don’t know go to this great web site to ID your system by plugging in your systems S/N EveryMac - Lookup let us know as well then we can aim you to the needed part and guide to put it in.
