I installed 2 x 2 gigs of this ram into my white macbook from 09, 2.13 ghz. I was running 10.5.8 when I made the install, but have since upgraded to 10.6.8. My battery is also shot, which may or may not be a related problem. It doesn't hold a charge longer than 10 mins, so I always have it plugged in. The computer has started freezing randomly, anywhere from 10 minutes of use to an hour, but usually it will freeze before an hour of use is up. I'm not sure if this is because of the ram, but it started around the time I installed the new ram. The screen will freeze, no response to closing the lid, no beach ball loading sign. The only remedy I have found is a hard shut down. I have made a habit of keeping Activity Monitor up so I can check the CPU usage, but the computer has been freezing whether the CPU is running at max capacity or not. This occurs when I'm using many programs (Logic, Firefox, iTunes, Word) at once, and also when I just have Firefox open. This computer is no longer under warranty as of a year ago. Any ideas? A reinstall of system software did not help, I'm worried that either my hard drive or logic board are failing.