[Ananda]

I know that this must sound like a silly question to most of you, but my mother in law was told that she should keep her computer (iMac) on all the time. Or else it will wear out. I have heard of this with wintel computers but not with Macs. Is this true?

[Kozmik]

It won't "wear out", per se, but the iMac draws so little power that leaving it on "sleep" mode all the time when it's not being used actually draws less power than turning it off and turning it on every day.

[RedRyder]

Apple say it's best to leave the iMac on always, to use 'sleep' mode when not in use, and that it's been designed as such. For myself, I'd switch mine to 'sleep' mode when I don't need it during the day rather than turn it on (boot it up) every time I need it. But if I weren't going to need it for more than a couple of days I feel it's best to turn off the power by using the 'Shut Down' command in the Special menu. You should always leave the power switch (on the wall) turned on otherwise you drain the battery on the motherboard and the computer will loose functions such as date and time and so on.

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"Greetings from
Cricklewood"

[pdjr]

not unless it's in your bedroom. even in sleep mode, the monitor seems bright to me.

[Scott_H]

Turn it on the morning and off at night. That's what I do. I turn if off if I know I'm going to be out for a long time too.

[el chupacabra]

...and what if there is a power serge or something while my imac is sleeping....buy buy imac ...buy forever

[sek929]

Leaving it on is far better for it instead of powering down and up each day, as for screen brightness when its in sleep mode the monitor completey shuts down and therefore emits no light. Only problem would be if the fan (if it has one) would bother you.

Not counting restarts my iMac has been "on" for about 2 months now.

And if there was a power surge it wouldn't matter if it was off just simply if the plug was still in the wall outlet (hopefully you have a surge protector) so even if it was off it would get zapped.

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[This message has been edited by sek929 (edited 04-17-2001).]

[fletch521]

My iMac is almost always on for two years now.

Fletch

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[suprz]

Originally posted by RedRyder:
[B. You should always leave the power switch (on the wall) turned on otherwise you drain the battery on the motherboard and the computer will loose functions such as date and time and so on.
[/B]

is that really true? will it really make the battery go dead faster than if you leave the power on? i always shut down my system when im not using it or not at home. and i always turn off the power tap/surge protector. if it does, any info on time frames? i've never heard anything about it using up the battery faster.

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" I think,
therefore....IMAC

[Kozmik]

The battery will run down if there's no power going to the machine (i.e. not having it plugged into the wall socket or power strip, or having the power strip turned off).

[as2]

My iMac has been on constantly since the day I bought it, apart from moving house, and while I was away on holiday for a fortnight.



------------------
Adam Skelton
------
Check out my new website...
www.toiletmaster.com

[suprz]

other than date and time, what other functions wil be lost, when the battery finally dies?

------------------
" I think,
therefore....IMAC

[Richard Clark]

The monitor control panel will not remember it's settings. View settings will be lost as well.

[PCTek]

Heh, yes, after a while, the constant spin-up and spin-down of the hard drive will wear it out. Yes, it is suggested that you keep the hard drive spinning all the time, thus, it doesn't need to spin up or down.

Also, i've heard that it takes MORE power to spin the drive up than it does to keep it running. So unless you want to drain more power, just keep the damn thing on all the time. It honestly doesn't hurt anything.

The only difference between sleep mode and shutdown (physically) is that the RAM is still getting power (to hold the contents), and the sleep light is getting power. If it's shut down, none of these are on, the whole machine is dead.

[confuser]

PCTek,

If sleep is almost same as shutting down, isn't the hard drive spinning down during sleep?

Just what exactly IS going on in the Energy Control Panel. I've always been a little confused on this. In fact, I use "Sleeper" just 'cause it seems a little clearer. It has an option for hard drive spinning down, along with monitor sleep and CPU sleep.

So what are really the recommended settings for the Energy Control Panel (and Sleeper, for anyone who uses that)?

Good thread, but the confuser is confused.

Leaving it on is fine, as long as there are no power interruptions. Power strip/surge protectors are JUNK!
Spend some cash on the best insurance you can get for your Mac...a UPS. Uninterruptable Power Supply.
New models are available now that will run on battery backup for a while, and if you're not available to do
a manual shutdown, they have software that will do it for you. It's about time too! PC's have had the software ability
for years, while we had none. I think the only one that has it right now is APC, but TrippLite might also.

Check it out. UPS has saved my Macs through storms and blackouts more times than I can remember...

just do it!

Lets face it. It doesn't matter if you turn it off or leave it on. It will be a outdated computer looooong before the thing dies regardless of your preference.

It was always explained to me by techies the reason for leaving a computer on all the time:

When you start up the computer the logic board and all the copper wiring / jumpers / processor heat up and remain warm while the computer is in use and this makes the metal expand a bit. When you shut down and it cools down the metal contracts. This happens over and over again if you shut down your computer every day and over time could cause the wiring to break or fail. It causes more stress than keeping the computer on and warm.

I'm sure everyone's parents lectured them about leaving lights on in the house, but what parents didn't know is that it uses more power to turn a bulb on and off several times in an hour than to just leave the light on the whole time. the iMac will use more power if it is turned on and off all the time and it 'causes stress on the power supply (surges at start-up) and the board as mentioned before.

My iMac has been left on for the past five months and I find it has less problems than my G4 at work which is shut down every night. The surge at start-up screws up my PRAM (it stopped remembering the time zone or time) and it is noisiest during the first hour until it warms up. I read that modern day monitors will not experience burn-in so that isn't an issue. Putting it to sleep will help it last longer. The only power use is keeping the memory in RAM retained.

Ah yes, another topic I can't resist. I feel qualified to give this advice after fifteen years in the selling, maintaining, and repairing of personal computer systems. The following applies to all brands of computers.

The "wearing out" referred to when cycling the power on a computer refers to the electric jolt and the expansion and contraction caused by warming and cooling on the circuits. This will shorten the life of a computer system; just as it will any other electronic device. However, I have not seen this cause a problem over the average two- to three-year lifespan of a computer.

My preference is to put a system to sleep in between uses unless it would be for an extended period, such as a vacation.

When put to sleep, a computer system should deactivate the monitor, spin down the drives, slow the processor (usually causing a cooling fan to slow or stop), and either maintains the RAM state or save the information to the hard disk.

It is best to leave a computer plugged into the electric outlet at all times to maintain the user settings (e.g. CMOS or PRAM), date and time. My recommendation is to also use a good surge suppressor for all electric and data connections (e.g. telephone and broadband networks). The computer equipment should be the only items connected to this surge suppressor; otherwise the purpose of the filter is defeated. During lightning storms it is a good idea to disconnect all connections and definitely don't use the computer for risk of electrocution!

One last note is electricity use. Putting the system to sleep or turning it off when not in use saves money and places less of a strain on the power grid. Especially if you live in California!

I believe I'm correct in saying that either leaving it on all the time and/or shutting it off when not in use affect the computer just about the same.

Years ago when transistors, resistors, capacitors, and the like were not built like they are today, people were advised to keep their computers on all the time... this was because when the power was turned on, an electric surge went through the system, eventually and possibly making certain electrical parts of the computers fail after 'x' amount of turn ons/offs. Nowadays, the power supplies and power switches have been modified to prevent this, and therefore it really doesn't matter whether you leave the computer on or off.

I think that's right. Pretty damn sure -- that's what I've heard from a number of sources.

I can't believe in this day and age you people are still worried about power surges when turning your computer on and off. You don't think they've figured out how to prevent this in decades and decades of computer design? Do you know how much testing has gone into motherboard design? (testing is much more stressful than turning your computer on and off). I'd like to see it documented that Apple has recommended you to keep your computer on.

And yes, as someone mentioned earlier in this thread, your monitor does still emits some light (and, therefore, is using power) when in sleep mode. The monitor DOES NOT completely shut down in sleep mode.

And the hard disk argument...you don't think the hard drive spins down when you put it to sleep? You don't think the HD is designed to spin down hundreds or thousands of times in it's lifetime.

And the cooling off argument...you don't think that motherboard cools off everytime you put it to sleep? Let's see, no HD heat, little or no processor heat...oh yea, it's cooling off. Maybe not as much as shutting down (pretty damn close), but a LOT cooler than running.

Sleep is fine for short periods, just TURN IT OFF if you're going to be away for hours at a time. THAT would conserve energy.

YES, use a surge protector (there are enough free ones floating around at Comp, CCity, BBuy, OfficeMax...and some are pretty good ones).

[macvillage.net]

It's always better to let your Mac sleep rather than startup and shutdown. Here is the reason: When your computer first starts up, regardless of the technological breakthroughs, it has a tiny surge of power on the motherboard. This is normal, but not very good. It doesn't damage the mother board, but it is also not good for it. By leaving it on, you minimize this shock to your system. Thus in a fact you do "ware out" your computer. This is not just a PC problem since Macs are esentially the same (just better) as far as hardware goes. Also you should note that very little power is used in sleep. Esentially power just continues to flow preserving the RAM contents. Your monitor is off and most drives also go to sleep to conserve power.

I personally leave my G3 on 24x7. It's rarely off. My rule of thumb is that if I plan to use it in the next 24 hours, I leave it on. If I am not going to be arround and there is supposed to be a storm, or if I don't plan on using it for prolonged ammounts of time, then I shut it off. My G3 has been running for months with only a few hours downtime (stormy nights). It is also very efficient, I turn of the Sony monitor, and just leave the G3 itself on in sleep, thus it uses very little power.

And BTW: Power surges still wipe out many good machines. They are still a huge problem. And look closely at what you buy to protect yourself. Many won't cover something like a lightning strike, especially those free ones, so be very careful. Make sure it is UL approved. Check out the power protection devices by APS, they are awesome. Have one and love it.. they have battery backup (22 min on a B&W G3, even longer on an iMac, awake that is) and they have non battery backup (cheaper). Those have a warrenty and are able to withstand very large surges, so you get great protection.


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MacVillage.net Owner/Webmaster http://www.macvillage.net
Macintosh Portal
Email, Free Tech Support, Web Space, Search, Directory, and MUCH MORE!

Edit: Grammar fixes!

[This message has been edited by macvillage.net (edited 04-18-2001).]

Some of you are saying the monitor still emits light when in sleep mode. This is true on all iMac models w/o a slot-loading CD/DVD/CD-RW drive. All slot-loading iMacs, when in deep sleep(the power light dimming in and out) SHUT OFF ALL POWER TO THE MONITOR. However, when the energy saver control panel is set to turn off the monitor only, it will still emit light.

[no use for a nick]

The only problem with 24/7 uptime for me is that my iMac DVSE puts off so much heat. Even in sleep mode it emits some heat through the top vent. Not a big deal if you have a room in your house dedicated as an office, but in my tiny dorm room, it may as well be a radiator.

nick

Hey "no use for a nick"! Wrap up some of last weeks pizza in tinfoil, put it on the top vent, set the iMac alarm for 15 minutes and call me when it's done.

I leave my Strawberry 333 MHz Rev D iMac on all the time. I got it more than two years ago and for a while I even left the monitor on. It's fine to leave it on, I have had no problems with the computer whatsoever and soon I will upgrade to a new iMac.

Now about leaving the monitor on (even with a screensaver)... My screen is starting to show some flicker, much like ancient monitors. That rock-solid image is no more since something is really wearing out. Of course, I notice this only if I stare at a bright pattern exclusively to check for flicker. The family doesn't even notice.

Go ahead, leave it on. Set the display to turn off (using Energy saver) after some inactivity, but the CPU itself and its peripherals don't really care.

[WDL]

Turn on any of my four Macs when I'm going to use them - turn them off when
I'm done and shut off their surge supressors.

My oldest Mac (Centris 660 AV) has had two batteries in 7 or 8 years (can't remember
precisely) and my Performa 6360 has had one battery in four years.

I can live with replacing batteries - I like the way the memory clears when you completely
shut down.

Everyone to their own preferences - this works for me.

WDL

Lightbulbs don't draw more power when you turn them on. That's a myth. Even if they did, the amount of energy required to keep them lit is huge in comparison. Turn them off when you leave the room.

(Yes, many incandescent bulbs die when being turned on. So use nice compact fluorescents.)

Computers these days (esp. Macs) mechanically last far, far, far longer than their useful lifespan as working computers. How many of us have gotten rid of Macs (or just put them in the closet) because they weren't fast enough and not because they "broke". Shut 'em down if you're not using them for a few hours. They start up so damn fast nowadays. Even in sleep mode they draw something like 7W, don't they?

I read somewhere that the iMac uses on average like 80 watts when it is running and 32 watts when it is asleep. Not that great a difference really.
Where is there a source saying how much power the hard drive uses in spin-up/spin down mode as compared to normal operation or after it has been spun down?

[Apocalypse]

It is commonly advised to leave your system on all the time and even though this, supposedly, causes "wear" on the hardware, someone mentioned above that computers are built for far longer than their realistic 3 year life-time (as you will know if you collect vintage macs like I do, everything works fine even though they may be 15 years old). I think that part of this is marketing to demonstrate system stability and wake-times.
Apple has always been big on this. Remember the Newton? I have a Newton Message Pad 2000 and its battery pack can suspend it in sleep mode for...I never left it that long but weeks to say the least. Now it is to demonstrate how OS X can wake in under a second (I haven't seen this because I run various web things from my iMac with OS X so I never let it sleep).

All-in-all this is a non-issue if there ever was one. It is probably best to leave your computer on 24/7 but the not waiting for boot issue is far more relevant than the potential hardware-wear issue. But that is just me,
Jeff.

[mehtajr]

The leave it on/turn it off debate has been around for ages and has led to what I consider to be one of the greatest old wives tales in computing (i.e. shutting the machine down is harmful). Here's why I think it's an old wives tale:

Turning your computer on will not break it. I've never seen seen a computer that died to this mysterious heat expansion... you can say it "contributes" to the problems, but in my mind you can make just as convincing an argument that drinking milk contributes to cancer. So, shutting your machine down at the end of the day and starting it up in the morning will not kill it. The machine will die of its own accord many, many years down the line (e.g., I had a Mac II that was started up and shut down many times daily that lasted until 1997, long after it had been obsoleted).

Look at it logically: if you leave your machine running at all times (i.e. not in sleep) the fan is on. The power supply is being taxed. The hard drive is spinning. Arguing that leaving a mechanical part spinning at over 5,000 RPMs AT ALL TIMES is better for its mechanical life than leaving is spun down when not in use is ludicrous; it's a mechanical part that will eventually suffer a mechanical failure. Why do you think high-end servers (that run at all times) are designed to have hot-swappable hard drives and redundant power supplies? Because running at all times is hard on any piece of hardware. So, I'd say leaving the machine on at all times is a bad idea.

That having been said, I think the best thing to do is put the computer to sleep and hardly ever shut it down. Why?

1. Waking from sleep is much, much faster than starting up (especially if you're running X).

2. Deep sleep mode cuts power to the monitor, spins down the hard drive, and on machines without fans (iMac DVs) is silent. The machine only draws enough power to keep the memory powered (well, except under X... the machine really seems to be more "resting its eyes" than deep sleeping).

So, you can get a much faster wakeup time and cut the wear on the parts of your machine (hard drive, fan, and power supply by lightening the power draw) by using sleep over shutdown (set the energy saver to put the machine to sleep after say 20 minutes of inactivity or so). So, I always leave my machine asleep overnight and between uses during the day, just because it's so much faster to wakeup from sleep.

If I'm going to be leaving town for a couple of days, I shut my machine down... after all, why leave it sleeping if there's no chance anyone will be using it for days on end?

And on the subject of surge protectors:

A surge protector is useless against a lightning strike. Normal surge protectors are only designed to protect against minor fluctuations on the line (which do happen normally, so it's always a good idea to have one), a lightning strike can generate a huge jolt of current that will fry your computer AND your surge protector. If you're worried about lightning, get a lightning arrestor installed in your house's electric box by the power company; that will protect your house against lightning strikes.

[This message has been edited by mehtajr (edited 04-19-2001).]

I have a bondi blue revision b 233 iMac that has been on since i bought it..never any problems. Sometimes I put it into sleep sometimes I use a screen saver. Someone stated earlier that non slot loading iMacs monitors
still emit light when put into sleep..bogus..my monitor emits no light when put into sleep other than the amber power button.

-spaz

[dirkpitt]

Eponymous wrote:
>>Lightbulbs don't draw more power when you turn them on. That's a myth. Even if they did, the amount of energy required to keep them lit is huge in comparison. Turn them off when you leave the room.

(Yes, many incandescent bulbs die when being turned on...

Actually, it ought to be the other way around. Switching the circuit *off* causes a near-infinite change in current with time, inducing a tremendous surge (details involve inductance, I believe). This can be witnessed as arcing in many electrical switches as the broken circuit tries to restore itself. More complex circuits may be protected against this, so whether my Mac experiences the same I don't know. But lightbulbs and light switches, certainly. It may be (my theory) that lightbulbs popping when switched *on* had been just about killed when switched off previously, but not quite because the tungsten had cooled enough to cheat death.

Turning things on isn't an infinite change in current, because of the inherent resistance of the circuit.

It's been some months since I looked at my physics notes but the above informal explanation about inductance should be correct in the basics. Please bug me for any more details!

-DEP

Incandescent bulbs don't use more energy to turn on. Fluorescents do so it's better to leave them on unless you are gone for a long period of time. The warm-up/cool down cycle is not good for any electronics, it's better to leave your stereo on all time as well though with cheap electronics it doesn't really matter. TV's and monitors have a slow warm up to lessen thermal shock.

I turn my Rev. A iMac off because the fan noise is annoying otherwise I would leave it on constantly.

[dirkpitt]

Oops, correction to my previous post. The current in circuits containing an inductance (a coil of wire--transformers, motors apply) rises slowly when switched on, because of the inductance (technically, the inductor *induces* a back-EMF that acts against the normal flow of current). I originally said it was the resistance that caused it--a big difference.

Also, switching off a circuit can be done without the huge power surge that is draining all of California's electricity, by connecting across the power leads first (a short circuit), then disconnecting the power itself. This creates a circuit with just the inductor(s) as the "power", and the current slowly decays to zero. The decay is slow this time, because of the resistance in the circuit and eventually all the electrical energy is converted to waste heat. I suspect modern appliances are probably connected up in this safe way already (I mean, why not?), but that is just speculation.

-DEP

[TimmyDee51]

I agree. I turn my rev. D iMac off at night because the fan is too damn annoying. My parents have a slot-loading iMac at home and we don't keep it on 24-7. I don't know where you guys are getting this "it takes more power to turn it on than to let it sleep" thing. If you don't specifically tell it to go to sleep, the monitor remains on, just with no picture. This wastes a lot of electricity. Also, I don't see how a minute and a half of full use draws more power than hours drawing watts asleep. It just can't be true.

Although its been refuted before, leaving your computer on all the time does not necessarily make for longevity. The circuits are just as adversely affected by heat on them all the time as they are with the supposed expansion and contraction. For example, heat is a primary concern in OCing a computer. The more heat, the shorter the life of the chip. If you take a smaller amount of heat and apply it over a prolonged period of time, you get the same effects: the metal gets stressed. The moral? Just turn it off when you won't use it for a number of hours.

[pliny]

speaking of which, has the powersupply on anyone's imac failed or had to be replaced? i ask because the slot loaders don't have a fan and i'm wondering how tough their ps's are without a fan to cool them. my hard drive spins all the time (unless sleeping or off) and the imac is on pretty much all day into the night--how long before this baby goes?

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"i look in your general direction"

[clifhirtle]

Energy-wise AND lifespan-wise it is better to leave any Macintosh manufactured in the last 1-2 years on (or in sleep mode) at all times. As others have pointed out, this is the reason for Apple reprogramming the default operation of the power button to put a Mac to sleep rather than shut it off. Mind you, there are definitely issues of machine stability with the Classic MacOS when you do not shut the machine down, but there is no doubt it is better energy-wise. Current Macintosh models are based on a similar (if not the same) motherboard architecture and therefore share the advanced power management capabilities one would normally only expect in a portable line of products. Apple has always been at the forefront of producing energy efficient and environment-friendly products.

To all those asking about the exact power usage of current Macs, here it is...

G4 Cube:
Max continuous power rating = 205W
Standby = 40W
Sleep = 8W
Off = 10W

G4 Tower:
Max continuous power rating = 338W
Standby = <90W
Sleep = <15W
Off = <10W

iMac:
Max continuous power rating = 170W
Standby = <93W
Sleep = <33W
Off = <4.2W

G4 Powerbook:
Mac continuous power rating = 45W
Standby = <20W
Sleep = <5W
Off = <4W

iBook:
Max continous power rating = 45W
Standby = <17W
Sleep = <4W
Off = <3W

22" Cinema Display:
Standby = <58W
Sleep = <3W
Off = <3W

15" Studio Display
Standby = <22W
Sleep = <2W
Off = <2W

17" Studio Display
Standby = <80W
Sleep = <8W
Off = <8W

Clearly these statistics show that not only do all current shipping Apple hardware products consumer extremely low energy in sleep modes, but in somes cases (Cube) consume LESS energy in sleep mode than when deactivated entirely.

PS: Those curious can find more information on the energy/environmental requirements of Apple products at:
http://www.apple.com/about/environment/

- C

[This message has been edited by clifhirtle (edited 04-21-2001).]