Chosen Solution
My MacBook Pro 15 (Late 2011) recently kicked it. I got stuck in a reboot loop. This happened while using a Thunderbolt cable to HDMI (not sure if this is relevant). I couldn’t get out of this loop. Deciding I wanted to update the drive to SSD, I went ahead and did so: Kingston SSDNow A400 480GB SSD I’ve since installed it and attempted a clean installing using a USB Sierra boot, which I created with Disk Creator. This is where I’m stuck, it loads, I can select the Sierra Boot, I get 3/4 of the way through the boot then it stops on a grey screen. Any suggestions to what I should try?
There are a couple of know issues with this machine. The first is the hard drive/IR cable. Replace it with the cable from the 2012 model. Do this first! MacBook Pro 15" Unibody (Mid 2012) Hard Drive Cable MacBook Pro 15" Unibody Early 2011 Hard Drive/IR Sensor Cable Replacement The second problem was the GPU. There was a repair program on it that has now expired: https://www.apple.com/support/macbookpro…
