Why is my backlight flickering?
I have a late 2009 21.5 inch iMac. The backlight flickers after a lot of use, and sometimes it just doesn’t work at all. The bottom half of the screen is yellower than the top half. I think that this may have something to do with the computer overheating, because I have vacuumed out a bunch of dust from the bottom of the iMac, and it works better for a bit, before the backlight starts flickering again. Does anyone have any ideas on what might be wrong, or what I might have to do to fix it? If so, any answers would be greatly appreciated.