Mayer 's tip is really good! At this model the RAM bracket holder often looses contact with the bottom side on the logic board (side you can not inspect without dismounting the mainboard). This leads to freezes, reboots, stripes and display errors. Re-soldering the bottom side of the RAM bracket holder is quite a challenge and often you will need to replace the whole mainboard (>400 USD !!!). Option 1: you can use only one slot (the top one usually). Option 2: If you want to use both slots (instead of only one - either top or bottom), you can try to put some distance between RAM bracket holder and top case. I solved this problem with a short strip of an old credit card. Put it between the RAM bracket holder and the logic board to help press up and a strip on the holder so the cover presses down. If you shake or bang your MacBook Pro or just type on the keyboard, the RAM bracket holder will not loose contact to the modules. Here’s a picture of the first test. With this place holders no freeze, no reboot,...