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I replaced the Hard Drive with a SSD and now screen looks broken. When I go to power up the machine, the screen is grey with a black bar in the middle and a black blob on the right of the screen. I can see the apple logo and my cursor in the middle black bar, but nowhere else. I did nothing to hurt the screen when taking out the connectors and when I was replacing the screen. Is the screen broken and will I have to get a new one?
Ouch! Not good ;-{ Sounds like you where a bit rough taking the display assembly off. The bar is where you severed the glass to ribbon assembly connection (not repairable) the blag blob is where you pressed something on the back side damaging the liquid crystal held in the sandwich of the two glass plates. For reference here’s the guide to properly take the display off iMac Intel 27" Retina 5K Display Display Replacement and the most important is using the correct tools iMac Opening Wheel Plastic Cards You still need to use the tools correctly as misuse can still damaged things. The guide offers the warnings and explains the proper techniques. You’ll still need a set of replacement adhesives if you don’t have them [linked product missing or disabled: IF174-005-1] Time for a new display assembly - Sorry