Power setting question

[eyeguy 54]

windows 7. I am on this thing a lot during the day. Always plugged in. At night I have it set to hibernate when I close the lid. Wondering if I should turn it off at night or is hibernate just fine. I like to check the weather when I get up and it pops on quick when in hibernate. Or would sleep be better? Or doesn't it matter? Thanks

[upnorth]

In windows 7 Hibernate works pretty good.

[eyeguy 54]

thx

[aanderud]

Hibernate is OK, but I actually prefer sleep over hibernate. It'll use almost no power in sleep mode, but it'll wake up and go back to sleep much faster than hibernate. The reason it's faster is the memory is still powered, so when you 'wake up' again nothing has to be loaded off disk. Similarly, when you go to sleep, nothing has to be written to disk. It makes for a much better 'on/off' experience -- literally a second or two in each direction, versus up to 15 seconds with hibernate, depending on how much memory you have to write/load to and from disk on the hibernate.

[Whoaru99]

I second Sleep over Hibernate. With Sleep you get almost as much power savings as Hibernate but with the much faster response that aanderud mentioned.

On the other hand, if/when you're running on battery then Hibernate or a full shutdown may be a better option because it uses no power.

[aanderud]

On the other hand, if/when you're running on battery then Hibernate or a full shutdown may be a better option because it uses no power.

That's right, hibernate uses no power, and sleep draws some due to the memory being powered up. I have actually had my work laptop it in sleep mode over a long 4 day weekend in the past and woken it up the next work day with something like 30-40% of my battery left. Or worse yet was when I left it sleeping over Christmas break (8 days or so) and I came back and it was completely drained to like 5%. I have since then configured it to hibernate after 24 hours of sleeping (when on battery). That way if it does get unplugged or if I throw it in the laptop bag and forget it, I'm not powering it up the next time with a low or dead battery.

One other thing to consider is that hibernate can be bad if you have an SSD (solid state drive). There are a finite number of write cycles on each sector on a solid state disk. When you hibernate, you write out all of your system memory to disk. That's 4-6 gigabytes, typically -- a lot of writing. Theoretically you will still get years out of the drive, especially if you hibernate only once per day, but if you configure your lid-close or power-button for hibernate, and you shut the lid every time you leave your computer (to get lunch, when you to go t-ball with the kids, etc), you're really writing a lot to disk and unnecessarily wearing on that drive.

[delcecchi]

I think hibernate does use some amount of power. My experience is that, on this laptop anyway, if I hibernate it for a day or so on battery it runs down significantly.

[Whoaru99]

Hibernate is not supposed to use any power by all accounts I've read. It's supposed to write the contents of RAM to disk then shut down.

[delcecchi]

OK, a test is forthcoming. I will hybernate this computer while unplugged and come back in morning. Right now 97% remaining

[delcecchi]

After 12 hours, was at 95%. I'm not sure that shows a trend, but it conforms to my experience. Some stuff is still powered, I believe.

[Whoaru99]

Based on a small test here, albeit with a desktop not laptop, your assertion about still some power consumption seems to have some legs.

Here's my test using my desktop/tower and a Kill-A-Watt meter (does not include monitor, only the computer itself).

Power Off = 0 VA

Power On viewing this thread = 102 VA (once processes stabilized)

Sleep Mode = 13 VA

Hibernate Mode = 11 VA

[upnorth]

Not a whole lot of (read that none) research on this as it matters little to me. But logic would say that if you only have to touch a key or move the mouse and not have to power it on, there must be a trace amount of juice running through the device to sense activity.

[Whoaru99]

On my computer I have to press the power button for it to come out of hibernate.

To come out of sleep requires only that I press a key on the keyboard. Perhaps wiggling the mouse would work too, but I normally just push the space bar.

[DTro]

I would bet any laptop battery will discharge slowly even if there is no power draw.

[Whoaru99]

Yes, all batteries have some amount of inherent self-discharge. For Li-ion I saw somewhere it was like 8 or 10% per month. Usually depends on temp too. Higher temp = faster self-discharge.

[delcecchi]

My experience is that hibernate discharges much faster than shut down. I learned that when going to cabin on vermilion. A couple days of hibernate pretty much kills battery.

[upnorth]

Well I remember from back in XP, and yes it is not a direct comparison as different OS's but anyways. We would get a few laptops that would gets stuck in hibernate and you couldn't bring them out of in any fashion, even holding the power button down (which after about 10 secs should initiate a shutdown) would it do anything. To break it out and get it going again we would unplug the power and remove the battery for a few minutes and plug everything back in and then start it up. So I would have to think at least back the XP days there was some power being consumed to keep it from restarting.

Not sure what the drain rate is for a battery sitting doing nothing these days, hard to think with modern batteries just sitting idle it would lose 2% overnight, but I guess it isn't out of the question.

Want to find out for sure if either sleep or hibernate requires power to maintain and recall a session, put into either mode and remove all power for a few minutes.

[SkunkedAgain]

I take my work laptop home in a laptop bag every night. I usually just shut down but was recently starting to experiment with sleep and hibernate. Do I need to worry about letting my laptop "breath" when in sleep in hibernate mode, or is there no heat generated and therefore the fans don't need to run?

[Whoaru99]

Fans not necessary in sleep or hibernate.

[aanderud]

My computer uses much less power in hibernate than it does in sleep, judging by battery consumption, but I would not be surprised that there is measurable power draw in hibernate. When I said "no power" earlier I was rounding down, and using sleep as a comparison. From my experience, I can hibernate more than a week on my laptop battery and still have 90% left. To me, that rounds down to "no power" compared to 'sleep', which consumes about 1/2 of my battery over a weekend.

Many computers (laptops included) will draw some power even if they're "shut down". Sometimes this is because it has wake-on-lan enabled, which can in some cases be configured to wake a "shut down" computer up as well as a sleeping one.

[Sandmannd]

If you aren't planning on using your computer soon, just shut it down. It's better overall for the computer. It will refresh it and run faster. Those that never shut down and only put them to sleep or hibernate will see a significant loss in speed over the course of a couple of days. Newer computers boot up so fast, it shouldn't be all that necessary to use anything other than shutting down.

[SkunkedAgain]

Newer computers boot up so fast

Obviously you've never owned a Lenovo

[Whoaru99]

Those that never shut down and only put them to sleep or hibernate will see a significant loss in speed over the course of a couple of days. Newer computers boot up so fast, it shouldn't be all that necessary to use anything other than shutting down.

I disagree on the first part. The computer I'm working on now rarely gets a full power down, generally only when I go out of town. Works fine from sleep mode.

Same with my work computer, although that I do power cycle roughly once per week just to see if they've pushed any updates that need a reboot.

And, about computer boot time...I still think that's a mixed bag. Yeah, machines are much more powerful, but programs are a lot bigger and more bloated too.