I have a new 27" 2020 iMac and. wondering how many of you just put yours to sleep vs a total shutdown. I had a 2011 model that I use to let run. Not sure the long term effects of doing either.
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Should I Shut down the iMac when not in use
- Thread starter Scarpad
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Mine is always sleeping. I believe iMacs were designed to be put to sleep when you aren’t using them.
Sleep is convenient and fast, and I am not aware of any negative long-term effect.
But I do shutdown quite often instead, as a convenient way of clearing memory caches from memory hogs like Chrome or Adobe apps.
But I do shutdown quite often instead, as a convenient way of clearing memory caches from memory hogs like Chrome or Adobe apps.
I always leave them running but have the display turn off after an hour. I have backup tasks that run in the middle of the night so I prefer to have them stay awake.
I'm always shutting down my iMac after finishing work. I've noticed some unusual CPU & GPU activity after waking my 2020 iMac from sleep and that alone is a reason to turn my computer off when I'm done with work. Not to mention that the fans might keep running (and they surely are in this alleged state of sleep on my iMac), thus contributing to dust build-up and unnecessary wear of the fan.
Regarding the spikes in CPU & GPU while in sleep mode, I'm seeing lots of messages along the lines of 'Service exited due to SIGKILL | sent by mds[82]' in Console.app. Also, both the CPU & GPU utilization are far higher compared to when I'm doing light stuff on my iMac (e.g. web browsing or running lightweight scripts). Anyone else seeing this? I've encountered this issue on Catalina and still happens under macOS Big Sur.
Regarding the spikes in CPU & GPU while in sleep mode, I'm seeing lots of messages along the lines of 'Service exited due to SIGKILL | sent by mds[82]' in Console.app. Also, both the CPU & GPU utilization are far higher compared to when I'm doing light stuff on my iMac (e.g. web browsing or running lightweight scripts). Anyone else seeing this? I've encountered this issue on Catalina and still happens under macOS Big Sur.
That's the bitcoin mining malware running in the background.
But the entire point of a cache is to make recently used information quickly available. Clearing the cache just means you'll have to wait for Chrome or Adobe apps to reload (from the internet or SSD) the data you need. Having your Mac's RAM be full is a good thing, not a bad thing.
I had a 2015 27" iMac 5K and had it always on 24/7 with no sleep with no issues, and been doing the same for the past 4 months on my 2020.
I have a 2009 iMac that has stayed on all the time (reboot one a week) and screen turns off after an hour. Never had a problem in 11 years
Have 3 2020 iMac and all set up the same way.
Have 3 2020 iMac and all set up the same way.
All my audio gear, computer gear (iMac, NUC, MacBook Pros), stay on 24/7. They go in sleep mode after 15-30 minutes (depending on the device). iMac fans only kick in periodically in sleep mode while it does background stuff for a minute and then goes back to sleeping. It's better thermally this way rather than cold and hot. I only restart for updates or if I have a problem. I also unplug during lightning storms or when out of the house for a long time. Otherwise, powered ON 24/7/365.
I'm surprised no one put some actual figures to it. They are all available here: Apple Link, select your product category at the bottom of the page, then your product.
For 2020 27" Retina 5k, it is:
For 2011 27", it is:
So sleep and off mode are relatively low consumption. If you leave it one full year in "off" mode, you need 0.45W*24h*365/1000 = 4kWh. That's between US $0.50 and EUR 1.20 for a full year.
In sleep mode, it is 12 kWh, which cost you US $2 to EUR 3.70.
On the 2011 model, you can set a timer to switch the display off before the unit goes to sleep at some specified time later.
While the display is off but the iMac still runs, the 2011 model consumes 42.5W, which would cost you 370 kWh, or US $50 to EUR 114.
You have lesser power consumption on a 2020 model with the screen on...
Worse if the 2011 is running with screen on. More than 140W, that's 1226 kWh a year (24/7 on with display), or US $150 to EUR 380.
So you can conclude that the old display is a power hog.
For 2020 27" Retina 5k, it is:
For 2011 27", it is:
So sleep and off mode are relatively low consumption. If you leave it one full year in "off" mode, you need 0.45W*24h*365/1000 = 4kWh. That's between US $0.50 and EUR 1.20 for a full year.
In sleep mode, it is 12 kWh, which cost you US $2 to EUR 3.70.
On the 2011 model, you can set a timer to switch the display off before the unit goes to sleep at some specified time later.
While the display is off but the iMac still runs, the 2011 model consumes 42.5W, which would cost you 370 kWh, or US $50 to EUR 114.
You have lesser power consumption on a 2020 model with the screen on...
Worse if the 2011 is running with screen on. More than 140W, that's 1226 kWh a year (24/7 on with display), or US $150 to EUR 380.
So you can conclude that the old display is a power hog.
During the day, let it sleep.
At night, shut it down.
Reboot in the morning.
At night, shut it down.
Reboot in the morning.
I'm sorry for the very basic questions.
How to turn off the monitor while keeping the iMac running?
Is it automatic, or need some adjustment.
How to turn off the monitor while keeping the iMac running?
Is it automatic, or need some adjustment.
Press Control-Shift-Eject to turn off the display.
Or, you can easily set up a "hot corner" to turn off display by moving the cursor.
In Energy Saver in System Preferences you can select the timeout for the display turning off as well the delay before sleep. I have the sleep setting to never and usually the display to 1 hour. When on a battery powered device you can set the settings differently when running on battery. I like 15 minutes for the display and 1 hour for sleep.
I found the culprit: it's called mediaanalysisd and seems to start when I don't touch the keyboard / trackpad of my iMac for like 5-10 minutes. What I also noticed is that disconnecting the iMac from the Internet will prevent the said process from running when the machine goes to sleep... Really weird.That's the bitcoin mining malware running in the background.
EDIT. Added the CPU and GPU graphs from iStat Menus.
CPU:
GPU:
Last edited:
I was wondering what others do with iMac when not using it. Before COVID I always switch my iMac off my last day off (work next day) and switch on when my first day off (day after work) and repeat. I don’t use iMac on my working days. I do my day off. Since COVID March 2019 I haven’t switch my iMac off even I am working but working from home (use pc laptop for work since they use windows only software). Only time it shut down and restart for updates only. It seem be fine. That longest I ever without shutting down. My iMac is late 2013 version.
Edit: Forgot say I put it on sleep when not using it.
Edit: Forgot say I put it on sleep when not using it.
Haha yes your right. Still not quite get used year 2021 yet so still thinking 2020 so 2019 year before.2020*
i have a 2016 iMac with ssdand running the mighty Catalina os.
during early morning hours our kitchen iMac turns its brawn from doing dinner recipies and youtube videos to a mighty network slave. It is doing home network backups via ChronoSync. I expereinced a lot if issues getting the mac to do this. Actually major battle but ChronoSync tech support helped a lot. Currently the imac does a delux job doing the backups w/o compermise.
I wake up every 6am and its like nothing happeded over night. The local news is streaming away plus I is see necessary successful backup status all sorta auto magic.
so
Much of the macOS's behavior around Sleep and Wake on Lan is not as expected due to apple's delayed maintenance on known issues software issues. I can say tho the iMac blends in well with all our new stainless steel appliances. iMac; clearly the wrong tool for the job.
where i live there are significatnt utility tap fees, taxes, surcharges so about ⅓ of my energy bill is spent before i burn a single nano watt. Why should i be concerned. Last year i installed an evaportive cooler. Replaced the boiler circulation pump with a varriable speed. these made a difference.
i do not shut the iMac down. I think the screen times out but that is about it.
during early morning hours our kitchen iMac turns its brawn from doing dinner recipies and youtube videos to a mighty network slave. It is doing home network backups via ChronoSync. I expereinced a lot if issues getting the mac to do this. Actually major battle but ChronoSync tech support helped a lot. Currently the imac does a delux job doing the backups w/o compermise.
I wake up every 6am and its like nothing happeded over night. The local news is streaming away plus I is see necessary successful backup status all sorta auto magic.
so
Much of the macOS's behavior around Sleep and Wake on Lan is not as expected due to apple's delayed maintenance on known issues software issues. I can say tho the iMac blends in well with all our new stainless steel appliances. iMac; clearly the wrong tool for the job.
where i live there are significatnt utility tap fees, taxes, surcharges so about ⅓ of my energy bill is spent before i burn a single nano watt. Why should i be concerned. Last year i installed an evaportive cooler. Replaced the boiler circulation pump with a varriable speed. these made a difference.
i do not shut the iMac down. I think the screen times out but that is about it.