Black screen at boot
I have an iMac intel 21.5". Recently, it has a screen problem. When I turn it on, the desktop starts, chimes, but nothing comes up on the screen. I hook it with an external monitor, picture comes up on the monitor, but the screen remains black. Can some body help? Thanks
You'll have to do more investigation. Shine a light at an angle from the front - if you see a faint image you have a backlight problem. This might be the inverter, or the CFL's, or controller (if it's an LED screen). Inverter/contro
If there's no image you could have a display data cable problem - more common and easier to replace, or, a bad LED/LCD screen (again a very difficult, but not as hard as a CFL tube) DIY repair.
Only you know how much money and time you want to sink in this machine.
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