Hey, I need some help. I upgraded my unibody MBP to 4Gb ram a few days ago, and I'm experiencing some strage things. It recognizes the ram, and it's running very good most of the time. Sometimes however, the computer freezes, and strange artifacts apear on the screen. I have to reboot to get it up and runnning again. I thought it might be hardware faliure in the ram, so I tested them with memtest86, but it didn't find any errors. The strangest thing is that there is no problem when I'm running on my windows partition (windows 7 beta). It's been running for 2 days now, and it usually freezes within 4 hours in OSX. Has anyone experienced anything like this?