In my case no kernel extensions. Every few days the computer freezes with a beachball and/or screen starts falling apart in large blocks randomly shuffling around the screen and I need to power it off. The first logicboard also added a bunch of pink noise in a few clusters all over the screen. Whenever I got close to freeze my power charging beeps were getting more and more frequent up to around 1 beep per 3 seconds with USB charger in (the beep when you insert power adapter into USB port).