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WOPR · Nov 3, 2006, 02:15 PM

Why is OS X still so flaky on this? From Jaguar through to my new Core 2 Duo iMac, many many times it doesn't go to sleep after the interval set in Energy Saver. Any idea why? It's set to sleep at 15 minutes at the moment and I've only got Mail and Safari open.

I can't even find a prefs file to trash.

SpaceMonkey · Nov 3, 2006, 02:22 PM

I haven't used Mail in a very , very long time, but the only thing I can think of is that maybe the auto-check mail option is keeping your computer awake? Maybe try turning that off or setting the auto-check mail interval to something longer than your sleep interval.

WOPR · Nov 3, 2006, 02:56 PM

I don't think it can be that because sometimes it sleeps when it should and at others it doesn't. Sometimes just changing the sleep time fixes it but not at the moment. This happens on every Mac I've owned in the last few years.

blackbird_1.0 · Nov 3, 2006, 03:34 PM

Check to see if certain processes are running.

WOPR · Nov 3, 2006, 03:42 PM

Originally Posted by blackbird_1.0

Check to see if certain processes are running.

Heh, anything in particular, that's a rather vague answer!

blackbird_1.0 · Nov 3, 2006, 03:53 PM

Programs, backgorund processes.

Use Activity Monitor. It's in /Applications/Utilities/

WOPR · Nov 3, 2006, 04:45 PM

I've checked and there's nothing unusual there, it just utterly refuses to go to sleep. I'll log out and in again. Again!

seanc · Nov 3, 2006, 04:53 PM

I don't think Mail can be causing it, it works fine for me on my PowerBook and has done on my iBooks. Throughout the years, what common piece of software have you been using, e.g little snitch or something?

WOPR · Nov 3, 2006, 07:11 PM

I have nothing unusual on my Mac, and I've installed nothing new lately. I'm perplexed, it just refuses to sleep on it's own.

jamil5454 · Nov 3, 2006, 11:00 PM

I've noticed that the Energy Saver preferences are sometimes flaky on my iMac Core 2 Duo as well. My display still dims after a few minutes of unuse even after I set it not to.

WOPR · Nov 4, 2006, 03:29 AM

Well I logged out and logged in as root, and it slept as it should. I logged back in as me and now it sleeps properly again. WTF?!

El Maestro · Nov 5, 2006, 11:23 PM

My PB 1.67 (10.x.x) has been kept awake by Microsoft's Auto-Update application for Office 2004. It only happens when there *is* an update available...I discovered this when my Powerbook wasn't sleeping after my designated interval and I restarted the Mac to see if that would help, and lo and behold the AutoUpdate window popped up and I instructed it to do the update. After that, viola, no sleep problems. This has happened consistently with each instance of an update to Office software. I don't know why this happens, but it does. Nothing else has kept my Mac awake.

EDIT: the same thing happens to the iMac G5 I use at work.

mishakim · Nov 6, 2006, 06:50 PM

my MDD g4 is completely unreliable as to whether it will sleep at the appointed time. Sometimes it does, sometimes it doesn't. I've pretty much written off figuring out what, if anything, makes the difference. It's probably due to some 3rd party software or driver, but who knows. It's just not worth the time to debug

steve626 · Nov 7, 2006, 02:38 AM

Originally Posted by mishakim

my MDD g4 is completely unreliable as to whether it will sleep at the appointed time. Sometimes it does, sometimes it doesn't. I've pretty much written off figuring out what, if anything, makes the difference. It's probably due to some 3rd party software or driver, but who knows. It's just not worth the time to debug

One experiment worth doing is to disconnect from the internet (disconnect hard wires, turn airport off on the Mac) totally. Then see if the computer sleeps when it should. I have noticed that with a laptop, and two iMacs, the processor tends not to sleep when on the internet ... something is talking to the computer, often a router or other network device (including other computers).

frdmfghtr · Nov 9, 2006, 01:43 AM

I have the same problem on my iBook G4 if I use the wireless connection on my college campus. Turn Airport off and it sleeps like a baby. Interestingly, if I'm at home on my Linksys wireless router, sleep works even with the Airport turned on.

Of course, closing the lid to sleep always works.

WOPR · Nov 9, 2006, 03:01 AM

Well it was fine for a few days but now refuses to sleep when it should again. I give up!

dpfenninger · Nov 9, 2006, 03:33 PM

I've had issues with the computer "bouncing" out of sleep when I manually tell it to sleep from the Apple menu. What I've found is that my USB hub and/or peripherals tend to be the culprit. Not sure if this will help you, but check out Peripheral Vision:

Peripheral Vision 1.6.3 - MacUpdate

It can show you visually when peripherals are connected and disconnected. For me, my media card reader seems to be keeping the computer from sleeping at times, as it's almost always the thing that shows up when the computer bounces awake again.