Hi,
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I just replaced my HDD in my late 2009 iMac with a new SSD. I followed a couple of different guides on how to do it. After I was done, I tried to turn on the mac, and it made the startup chime, and the screen turned on (I'm assuming because it went from black to gray). However, when I try to boot it with Command, Option + R + P or any of the other combinations, nothing happens(The screen just stays gray.)
I thought it was a problem with not having a bootable macosX version, so I used my Macbook to setup a bootable macOS High Sierra USB Install drive. I then plugged it into the iMac and used Option + R, but still the screen just stays gray.
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I double checked all of the cabels, and they are in, but when I was putting (What I think to be either the V-sync or lcd cabe) it was a bit finicky.
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Any help would be greatly appreciated!
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