Here's a fact: You can put a MacBook to sleep via the Apple menu, closing the lid or keeping it inactive for a certain amount of time. Here's my situation: I can put my MacBook to sleep via the Apple menu. I then need to press a key from the keyboard to wake it. That works. I can put my MacBook to sleep by closing the lid. I then need to open it again to wake it. That works. Now here's the problem. The thing won't go to sleep by itself. I've only noticed this recently. I used to be able to leave it inactive for a short while, the screen saver would kick in, later the screen would turn off and then it would go to sleep. How do I know? The white sleep light blinks and I have to press a key to wake it. What happens now? I leave it inactive, the screen saver comes up, then the screen goes black with the sleep light on but it is solid. As far as I know, it's still running full power, just that the screen is off. How do I know? I can wake it by moving a mouse or the trackpad, it's simply not sleeping. The hard drive is still spinning. I don't hear it "waking up" as it would normally. This is rather annoying because it uses a lot more power than it would had it been in sleep mode. Now, I know resetting the PMU would probably fix this but I would like to know if it has something to do with the system preferences before I do that. Here is the energy saving profile I use in the attachment.