I ordered 16 GB of ram (2x8GB) for my macbook (late 2011 13in 2.4 core duo), installed it and the machine boots up but eventually freezes on the apple screen with the boot spinner. I spent some time googling to no avail, so maybe someone can offer some assistance here. After the usual, reseating the ram, etc, I was able to boot into a DVD based linux distro and run mem test and use the system in text mode without any issues... until... I ran startx to start the graphical interface which leads me to think it is a video card/driver issue. I booted into single user mode, and again, I'm not sure, but I believe that the system freezes when it changes into a different video mode. I couldnt' find any info anywhere on this happening. Eventually I installed one 8GB card and one of the original 2 GB cards. OSX boots flawlessly with 10 GB ram. I'm really stumped as to how this could work. I had a theroy that perhaps since the new ram is rated 1333 Mhz and is presently running at 1067Mhz that maybe the older chip forces a lower speed on the more capable chip and that while the logic board can handle the full 16 GB mem, it glitches with the video card at a higher speed? This is all speculation. If anyone has any suggestions, I would greatly appreciate it.