May be its me, but I had a right issue with this, I then noticed the screw I loosened in step 10 was bending over. I removed the screw completely, logic board came out, and the metal pillar on the underneath of the board where said screw went in was bent. When I put it all back together afterwards after changing the drive, that long screw was bend, on straightening everything up, the pillar snapped off the logic board. Everything tightened up and its booted up fine. It might just me not following the instructions properly though