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Should I always leave my iMac on?

I read in other forums (MacNN, etc.) that it's a good idea to leave your iMac on all the time because OS-X does maintenance work (nightly, weekly and monthly), is this correct? By doing so, won't it wear down the computer faster (MTBF)?

Thanks,
Gemigene

iMac 17" Intel Mac OS X (10.4.7)

Posted on Aug 6, 2006 2:05 PM

Reply
25 replies

Aug 6, 2006 2:17 PM in response to Gemigene

User uploaded fileIt's a hot topic here too.

I leave mine on all the time since I use it at all hours of the day and night. The only time I turn mine off is when I am leaving town for a few days. I have everything plugged into an APC brand UPS so I am as protected as I can reasonably be.

I do unplug everything if I am going to be gone for a few days.

I got into the habit of leaving it on because of OS X's maintenance scripts that run overnight, but if you arre running 10.4.3 or later, they now run at the next available time if you Mac is off or asleep when they are scheduled to run.

The MTBF is s great that you would have to keep your Mac on for a lot longer than people even own them for, so I think you are safe. In any case, the most stressful time for a computer is the startup and shutdown process due to the thermal expansion and contraction.

No real harm either way, but it seems silly to me to start up and shut down your computer 6 times a day. Turn it on in the morning and shut it off at night - or leave it on all the time.

Aug 6, 2006 6:35 PM in response to Gemigene

Hi Gemigene,

I have been following posts like yours for the right answer or best answer...

If you mean 'it's a good idea to leave your iMac on all the time' to never allow your machine to go into sleep mode, many users do that and generally harmless to your iMac. I have actually been advised to never let my mac go into sleep mode by an Apple Specialist.

I did this, I set my iMac to never sleep but for display to sleep, for 4 weeks. I did shut down the machine on the average of once every 4 to 5 days for an hour of so before restarting. I had no problems at all, but I did notice the CPU temps were consistently higher at all times. The average temp when waking display after a few minutes or even over night, would always be @ 130 - 132 F, average CPU temps while working would be @ 138 - 142 F. My iMac also became slightly louder, just enough to notice but not enough to become alarmed.

Presently, I am now in the 3rd week of allowing my machine to go into sleep mode. I have found wake up temps can be as low as 120 - 122 F, my average working temps are usually between 132 - 136 F and rarely go above 142 F even when doing extensive photo editing. The mac is a bit quieter.

My personal conclusion, let your computer go into sleep mode but completely powering down every day is not necessary and may actually do more harm than good, in relative terms of course... 🙂

Rick

iMac G5 iSight 20" - 30G iPOD in Slimming Black - Mac OS X (10.4.7) - HP Pav 15" WS and Toshiba Sat 17" WS LP's - Canon 20D & A620

Aug 6, 2006 7:20 PM in response to Gemigene

The answer is yes and no...

Obviously if you Mac goes to sleep it probably cannot perform auto tasks at the selected times, but as Eric pointed out in his post, the auto task will be performed at the next available time...

Rick

iMac G5 iSight 20" - 30G iPOD in Slimming Black - Mac OS X (10.4.7) - HP Pav 15" WS and Toshiba Sat 17" WS LP's - Canon 20D & A620

Aug 6, 2006 8:22 PM in response to Gemigene

this is a hot topic here.
ive read many posts.
after the last post i read i will continue to turn my computer on in the morning and off at night. ( or as long as im going to use it )
i hate to think of being at work and having a storm roll through with lots of lightning, while my mac was sleeping.
Lately there seems to be power problems everywhere here in the US.
Surges,Outages ect.
so like i said if im done using it for the day i turn it off.
also every little bit i can save on utility bill helps !

Aug 6, 2006 9:33 PM in response to Dah•veed

true
very true
i have always been one to say make sure its on a surge protecter ( a fuse and reset button not just a power strip )
and if lightning hits your house or close to it even surge protectors wont help
i also protect phone line !
heard to many stories of that one LOL
later................

ps
i should of said that in my post
even though i turn off i still have as much protection as possible

Aug 6, 2006 10:14 PM in response to bmoraski

I went through a long phase of leaving my iMac on all the time, letting it go to sleep after twenty minutes of inactivity. Lately, I've started to power it off at the end of the day and turning it back on the next morning (or whenever I'm going to use it again). My electric bill has been horrendous this summer. I make a point out of turning off unneeded lights so I just decided that leaving my iMac on all night, even if sleeping, just didn't make sense.

Regards,
Steve M.

Aug 6, 2006 10:17 PM in response to Marty J

some one posted ,not to long ago, about power savings when you don't run the computer all the time ie sleepmode

ive had the "should i turn it on or leave it off on back in my Amiga and Early PC days.
yes the amiga ! anybody remember ?
i have to watch every penny in my single income household with wife and 2 kids
i dont leave ANYTHING on that doesnt NEED to be on !!!!!!!!!!! LOL

Aug 7, 2006 9:26 AM in response to Gemigene

I leave my iMac on all the time (except when away), but for a reason that hasn't been stated. A few years ago I read that the computer's hardest work is turning itself on, since the startup procedure checks every component. Does starting/stopping the computer everyday shorten the life-span of some components as is my assumption?

Jim

P.S. Yep, I remember the Amiga -- never owned one, though. How about a Kaypro? Anybody ever heard of that one?

Aug 7, 2006 9:33 AM in response to JimHarrington

Jim,

I think this is a question that could be tossed back and forth from now on. I really doubt anyone knows whether the "wear and tear" of booting on and off is of any importance in the lifespan of a home computer. How this weighs against leaving it running constantly is just a guess in my opinion.

I have rethought this in regards to my own use and now turn my iMac off every evening after I finish using it. I just can't see the merit in wasting the energy in keeping it on when I'm not using it. I turn off all unused lights at night (and during the day too) so I figure I would do the same with my iMac.

Regards,
Steve M.

Should I always leave my iMac on?

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