If every time you boot your Mac, the Memory Slot Utility opens with an alert stating “Memory modules are installed in the recommended slots”, perform these steps to prevent this from reoccurring: Enable the root user (if not already enabled), log into OS X using the root user account, close the Memory Slot Utility when the alert comes up, then reboot. This issue has been reported with Mac OS X 10.5-10.7, and appears to be caused by the Memory Slot Utility (located in /System/Library/CoreServices) not having permissions to clear the message.