How do you set power options (turn off hard disk/standby/hibernates)

I don't know exactly the difference between standby and hibernates... How does one set these 3:

Turn off hard disk
System standby
System hibernates

Which one is supposed to be before (or after) which one?

 

Timings should be set in increasing minutes in the order you have listed (hard disk, standby, hibernate). This is because if the computer is in standby the drives are already off, and if the computer is hibernated it cannot standby.

I set a relatively low number for hard disk (5-15 minutes), and have one set for both on battery and AC.

I set a moderate number for standby (≈15 minutes for battery, and ≈90 minutes for AC).

I set a very long number for hibernate (≈600 minutes for battery, NEVER for AC).

I also have my screen turn off when on battery after ≈5 minutes in my bright screen profiles (e.g. "Sunny Day" with maximum brightness at all times).

I also have my computer go to standby when I close the lid (only on battery; on AC it keeps running). Additionally, pressing the power button puts my computer in standby, and the icon on the start menu is shutdown.

My theory is that hibernate is actually counter-productive for less than 6 hours. The reasoning goes as follows:

• Standby is very quick to sleep and wake up (<5 seconds usually).
• However, standby draws a token amount of power (<1 watt) to keep data in RAM and allow you to resume).
• Conversely, hibernate is very slow (>60 seconds) to sleep and wake up (especially if you have lots of RAM and/or a slow disk)
• Hibernate draws no power. However, it takes a substantial amount of power to write the entire contents of RAM to disk, and then read it back again.
• Therefore, there is a crossover point where hibernate is better on the battery than standby, but I believe it to be fairly large (>6 hours).

Additionally, notebooks are designed so that if the battery gets very low (e.g. <5%) when on standby, it will wake up and hibernate automatically (to prevent a loss of data when the battery hits 0%).

I use standby frequently, but only use Hibernate when I plan on leaving my computer unplugged/idle for a few days but don't want to shutdown (I usually use Fn+F12 to achieve this).

 

Jon, many thanks for the thorough reply!

One question: why do many people (including you) not shut down their laptops for days, weeks or maybe months?

 

because you dont need to shut down PCs/laptops.
just standby (or hibernate) them when you go
away.

 

Don't need to in most cases (any OS using the NT Kernel [Win 2000+] or Linux is stable). I only reboot when I want to switch operating systems, or am required to because of a software update.

Additionally, I find that on my computer, the biggest slowdown is the boot up, and especially the first 15 minutes after booting. Vista uses a Superfetch cache that populates your RAM with files/programs it thinks you will want. This is effective, but it makes the first few minutes after bootup very slow as it is spooling data off your disk to populate the cache (6 MB/s in my experience). Once the computer is up and running (or after a standby resume) everything runs very fast (the cache is already populated).

 

Thanks for both replies! It seems the main reason for not shutting down is for convenience. If, however, convenience is not concern (suppose I don't mind the extra time to turn it on and get back to previous screen etc), would there be advantage of shutting down over not shutting down, or vice versa? E.g. as far as the life of the computer is concerned? Isn't it better to have it in complete "rest" than not? Also, isn't the computer more prone to have various problems (either hardware or software) while it's on than while it's completely off?

 

It is primarily a convenience issue.

I am not sure of the exact nature of your question. Some people have noted problems after resuming from standby/hibernate (I've never had one), but even if these occur a full reset almost always fixes it.

The biggest reason to go for a full shutdown (or hibernate) is that it stops power drain. Under standby (more accurately S3), a token amount of energy is used to power the RAM as this is volatile storage. Everything else (drives, CPU, etc.) is in the same off state as when the computer is completely shut down.

 

I tend to agree with the other responses here, with a couple of differences:

I've heard that Windows (at least XP, don't know about Vista or Win7) likes to be shut down and restarted once in a while... helps to kill processes that don't self-terminate as they should when a program ends, reallocates deleted disk sectors and such things. Consequently, I suspend (close the lid) when I'm going to be away from my laptop for an hour or couple of hours. Longer than that and I hibernate it (Fn+F12). Once a week or so, I actually shut it down and restart it the next day.

Regarding shutting down the hard disk to conserve battery power, I read somewhere on this forum that it's hard on disks to shut them down and power them back up, so the advice was to disable hard disk shutdown on both battery and AC power setups. I followed this advice because it sounded good, not because I have any 1st hand knowledge to back it up.

I hope others chime in on this thread...

 

Thank you very much, Jon.

 

I don't think it has much effect on drive life, but powering them up/down frequently is not great.

In fact, a very low hard drive spin down time (e.g. 30 seconds) would actually be counterproductive from a power management standpoint as there is a substantial amount of energy consumed in the spin up phase (≈5 watts iirc) vs. continuos idle operation (usually <2 watts).

For an SSD, there should be no real effect from this setting at all. SSDs enter a low power state whenever they aren't being accessed, and because they are solid, there aren't any platters to spin down.

All these things being said, I actually have found it almost impossible to force a drive to power down in Windows Vista. The prevalent use of caching, indexing, and automatic de-fragmenting means that the drive is almost constantly accessed (albeit at a limited level). Despite this, I get substantially better battery life (≈ 2 watts) under Vista than XP (where drives actually will spin down).