never put iMac to sleep

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Hi everyone

My 27" iMac is my main computer - it holds all my documents, music, films, photos, etc.

At present I am using my newly acquired macbook air much more but store everything I do on my iMac. I also use it for home sharing which entails having iTunes switched on. This entails asking someone to wake it for me but there's not always someone here.

So, my question is whether it's safe to leave my iMac in its never sleep mode or is this unwise?

Thanks, Nick
 
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I never use the sleep mode on either my PC or iMac and haven't had any problems. It certainly isn't a safety issue as far as I am, aware.

I suppose the purists would say that it isn't very green but what the ****!
 
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MacInWin

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Nick, what I would do (and have done here) is have the CPU never sleep, but let the display sleep. That way the system is constantly connected and available for home sharing, but the big power hog, the monitor, is not burning up your money.

I keep it that way because I use the iMac as a driver for my home automation and don't want not to have it available when I want to change something from my iPhone app. My iMac has been in that mode for close to four years.

I also have the iMac set reboot on power and to login automatically and the home automation software in the boot up sequence so that if for any reason the power fails, it will reboot when power returns and resume home automation control. On my iMac, running Mavericks, it's under System Preferences/Energy Saver, check the box "Start up automatically after a power failure."
 
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chas_m

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It's okay to have the Mac not sleep if that's what you require. It does use a bit more power (since the hard drive and CPU don't get to rest) but this is not a huge amount.

If you can identify specific things you need to have on both machines and just want to keep them in sync, you could look at something like Chronosync to do that.

Alternatively, you could have someone set the iMac to wake on network access. That would let it sleep when you're not using it, but wake up when you try to connect with it from the MBA.
 
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MacInWin

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On the power front, I just ran a quick test on my iMac. Power on, screen dark, it draws 45W, with screen on, it jumped to 105W. So with it on and screen dark, it's not terribly wasteful of electricity. At 45W, it's drawing 39.5 KWH per YEAR, so you can get what you are paying for electricity and calculate what it costs to run your iMac continuously. At my rates in Winchester, VA, where it averages US$0.10 per kWh, that works out to be US$3.95 for the year (current exchange rate makes that about £2.62 GBP per year). I don't know what your rates are, Nick, but from a quick search of UK electricity prices, it looks to be higher for you. I saw £0.13 per kWh in London, which at current exchange rates works out to be about US$0.19 compared to my US$0.10. So even if we assume it's double my rate, that still works out to be less than US$8/year for you, or £5.31. YMMV, of course.
 

pigoo3

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...that works out to be US$3.95 for the year …

Hopefully I didn't make a mistake. According to my math I get $39.50.:)

- Nick
 

pigoo3

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Nope, it's $3.95 (39.5 kWh * 0.10). Check your decimal point!

Here's my math:

- 45w/hour x 24 hours = 1080 watts/day
- 1080 w/day x 365 = 394200 watts/year
- 394200 watts/year divide by 1000 to convert to kw = 394.3kw/year
- 394.3hw/year x $0.10/kw = $39.42

$39.42 electrical cost/year.

- Nick
 
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MacInWin

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ARGGH! I dropped a decimal point in calculating the kWh. You are correct, it's 394.2 kWh/year and so then $39.41/year.
 
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Thanks everyone

I'll work out the cost to see if it's prohibitive and if so leave it at the max of 3 hours it's at now
 

pigoo3

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I dropped a decimal point in calculating the kWh.

No problems man. Either way…was just curious & wanted to know the exact answer.:)

- Nick
 
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I turn my iMac off every night for some reason. Sleep for my macbook and turn it off about twice a week.
 
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I turn my iMac off every night for some reason. Sleep for my macbook and turn it off about twice a week.

Hi Nancy........ - not sure if the above is just a statement or a possible question? Plus, 'off every night for some reason' is not clear?

If you are wondering about turning your computer off or leaving the machine on, the take a look at this recent related THREAD, which you may have already seen. Dave :)
 

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