Please Explain Power Schemes in XP Home's Power Options Props

[Jeffrey L. Hook]

Can anyone either explain the confusing settings in Windows XP's Power
Options Properties dialogue, or refer me to an intelligible on-line
explanation? The Power Options dialogue's found in Control Panel. It can
also be reached via the "Power" button on the "Screen Saver" tab in the
Desktop's Display Properties dialogue. (I'm running XP's Home Edition with
SP2.)

The Power Options Properties "Power Schemes" tab lists four settings:

1. monitor off,
2. hard drive off,
3. system standby, and
4. system hibernation.

The "Power Schemes" contextual help feature provides two separate "tool tip"
explanatory texts for each of those four settings. Click the help cursor on
the "label" for any of the settings, at the left side of the "page," and
you'll be shown an explanation which makes no distinction between portable
and desktop systems. Click the help cursor on that same setting's "field"
itself, at the right side of the "page," and the help text will explain that
the setting is used when the system is "running on AC power," which suggests
the setting's relevant only to battery-powered systems.

I don't understand the relationship of the time intervals for hard drive
shut-down, for system standby, and for system hibernation. I'm assuming a
system can't enter standby or hibernation if its hard drive has already been
powered-down first. Can a drive which has been powered-down be "repowered"
in order to put the system into standby or hibernation? How can a system's
state be preserved (with respect to programs which were running and with
respect to folders and files which were open) if a drive shuts down *before*
the system enters standby or hibernation?

Thanks.

Jeff Hook, NJ, USA
(I've cross-posted this message to the Windows XP Hardware group, to the
Windows XP Help & Support group, and to the Windows XP Performance &
Maintenance group.)

 

[M.I.5¾]

Can anyone either explain the confusing settings in Windows XP's Power
Options Properties dialogue, or refer me to an intelligible on-line
explanation? The Power Options dialogue's found in Control Panel. It can
also be reached via the "Power" button on the "Screen Saver" tab in the
Desktop's Display Properties dialogue. (I'm running XP's Home Edition
with
SP2.)

The Power Options Properties "Power Schemes" tab lists four settings:

1. monitor off,

Sends a signal (or more accurately removes a signal) that causes the monitor
to enter its standby mode (saving energy and the backlight life).
Generally, pressing a key or moving the mouse causes the monitor to spring
back to life.

2. hard drive off,

Turns off the hard drive's motor and parks the head. When the drive needs to
be accessed, the drive motor has to first spin up again before data can be
recovered. The drive's firmware does not have to be reloaded so this is a
little quicker than when the drive is first turned on. There is much
controversy over whether starting and stopping causes more wear and tear
than just leaving the drive running. We have examples of disk drives that
are nearly a decade old that have never been switched off.

3. system standby,

Turns off almost all of the system, but retains the RAM contents. The RAM
is kept alive by the 5vSTBY output from the power supply. When windows is
restarted, it pretty well carries on where it left off. The only down side
is that an interuption in power will cause everything being worked on to be
lost (unless a save was made prior to standby).

4. system hibernation.

Almost the same as Standby except that as part of the hibernate process, the
contents of the RAM are written out to a file on the hard disc drive. When
windows is restarted, the first thing it does is look for this file and if
it finds it, reads it back into RAM. Windows then restarts as though
recovering from standby. The advantage of this mode is that a power
interuption will not lose anything being worked upon. Many users shut down
to this mode because restarting is much quicker than a full reboot.

 

[Leonard Grey]

XP's Power Options were intended for laptops, which frequently use
battery power. They also work with desktops, but with varying degrees of
success, because the hardware is different from a laptop.

This article contains a good explanation of the various power saving
states in Windows XP:

"To Sleep, Perchance To Hibernate..."
http://www.informationweek.com/story/IWK20020927S0028

 

[Jeffrey L. Hook]

Thanks, M.I.5¾.

You said:

We have examples of disk drives that are nearly a decade old that have
never been switched off.

I'm aware that many systems are never shut off. I'm concerned about the
environmental effects of the use of electricity. I'm much more motivated to
reduce power plant emissions than to extend the life of my hardware. I'd
like to use my system's standby and hibernation capabilities as much as I
can for the benefit of the natural environment. I may be wrong about this,
but I think the service life of hardware devices may only be extended
negligibly if the devices are operated continuously. If that's true, then
the environmental cost of the extension of service life doesn't seem to be
justifiable.

Can we say that each of the four time-related settings on the "Power
Scheme" tab of the "Power Options Properties" "dialogue" or "sheet" refers
to a "device power-state change" which the system will make after an
interval of time which the user has chosen?

Your explanations of how the system makes each of those "power-state
changes" suggests an answer to my questions about the sequence of events,
and about how certain events can occur if the system's hard disk drive (HDD)
has already been powered-down. I said:

++++

I don't understand the relationship of the time intervals for hard drive
shut-down, for system standby, and for system hibernation. I'm assuming a
system *can't* enter standby or hibernation if its hard drive has *already*
been powered-down *first*. Can a drive which has been powered-down be
"repowered" in order to put the system into standby or hibernation? How can
a system's state be preserved (with respect to programs which were running
and with respect to folders and files which were open) if a drive shuts down
*before* the system enters standby or hibernation?

++++

These topics have been brought to my attention by a problem which I
experienced after I installed a new power supply unit. My system seemed to
enter standby automatically as I'd previously set it to do, and it left
standby in response to mouse movement, as I'd also previously set it to do,
but it seemed to be unable to restore its prior state. Instead, it
rebooted. I began to inquire about these "Power Schemes" settings in my
draft inquiry about my specific "system reboots from standby" problem, but I
thought I could increase clarity by breaking this topic out from the details
of my current problem. I'll start a new thread for my current system
problem in these same news groups later.

It looks like I failed to understand the role of RAM in the recovery of the
system's previous state from standby. I also seem to have misunderstood the
basic operation of the HDD.

Am I correct in assuming that the HDD does provide "permanent" data storage,
but its contents can only be read "in the moment," and that, to be available
"continuously," they must be stored either in RAM or in... hmmm....
"hiberfil.sys", which is merely a system file in the root of the selfsame
HDD... hmmm...

I'm still confused, but it seems I was wrong about assuming that the system
*couldn't* enter standby or hibernation *after* the HDD was powered down. I
now assume the HDD can be "switched on and off" without affecting the
system's restoration of its prior state from standby (for which it takes
data from RAM) or from hibernation (for which it takes data from
hiberfil.sys, on the HDD). I guess this suggests that, yes, the HDD *could*
be powered down first, but the system could later enter hibernation. Would
the system *always* store information about its prior state in RAM when the
HDD was powered down, and would the system then automatically power the HDD
back up in order to record prior state information to hiberfil.sys, or is
that too "baroque"? Is hiberfil.sys *always* used to store prior state
information, at *all* times, so the system would always be able to restore
its prior state directly from that file?

You offered this explanation of the system's use of RAM for its recovery
from standby:

++++

3. system standby

Turns off almost all of the system, but retains the RAM contents. The RAM
is kept alive by the 5vSTBY output from the power supply. When windows is
restarted, it pretty well carries on where it left off. The only down side
is that an interruption in power will cause everything being worked on to be
lost (unless a save was made prior to standby).

++++

Your explanation suggests that my system's apparent inability to restore its
prior state upon recovery from standby after the installation of a new power
supply unit *may* suggest that the new PSU *isn't* supplying power to RAM
correctly. Is that possible? If so, this thread may already be done, and
it may be appropriate for me to start a new thread in which I can offer the
details of my system hardware, etc., in case they're required for an
analysis of my "system reboots from standby" problem.

I'd be delighted, however, if anybody else chooses to add to this current
thread. Many other users may wish to know how we can use system power
management to reduce the environmental harm which is done by much of our
production of electrical power.

Thanks,
Jeff Hook, NJ, USA

 

[Jeffrey L. Hook]

Excellent, Leonard. Thanks. This helps to explain the reference to AC
power in the second of two tool-tip type contextual help texts which is
offered for each of the settings. I shouldn't be snide, because I don't have
any programming skills. Creating an OS must be a gargantuan job, and the
results aren't likely to be perfect, but, gee whiz, the use of power
management controls which simply don't work reliably doesn't seem
appropriate to me. Then again, it may be best to think of Windows as "a
work in progress"... After all, "it's only human to err..."

Thanks for the cited reference.

Jeff Hook, NJ, USA
(I've cross-posted this message to the Windows XP Hardware group, to the
Windows XP Help & Support group, and to the Windows XP Performance &
Maintenance group.)



XP's Power Options were intended for laptops, which frequently use
battery power. They also work with desktops, but with varying degrees of
success, because the hardware is different from a laptop.

This article contains a good explanation of the various power saving
states in Windows XP:

"To Sleep, Perchance To Hibernate..."
http://www.informationweek.com/story/IWK20020927S0028

 

[Leonard Grey]

I wasn't involved in the development of Windows - which works to
everyone's benefit - but I want to remind you that in XP, power options
were conceived with laptops in mind. (Don't know about Vista.) A laptop
has different hardware and a different BIOS from a desktop. It's
commonly known that power options don't always work well in desktops,
and that's largely a hardware issue.

 

[Jeffrey L. Hook]

It's commonly known that power options don't always work well in
desktops, and that's largely a hardware issue.

Yes. If you wish, "stay tuned" in these same groups for my upcoming
separate thread about my current system's apparent inability to return to
its prior state after I replaced its power supply unit this past Saturday.
You can see in my reply to the prior message in this thread from M.I.5¾ that
my new PSU *may* not be supplying power to my RAM correctly. (It seems more
likely that Windows XP's Home Edition isn't using the PSU's capability
correctly.)

I've also discovered Herman van Eijk's "MCE Standby Tool," which is
discussed
at:

http://www.xs4all.nl/~hveijk/mst/indexe.htm


and in this thread at The Green Button:

http://thegreenbutton.com/forums/1/237513/ShowThread.aspx


Van Eijk said, in message 06 on 5-22-06 at (using the acronym "MCE" to refer
to "Media Center Edition" systems):
http://www.avforums.com/forums/showthread.php?t=344643

....The primary goal of the MST project is to put as many MCEs as possible
properly in and out of standby (my contribution to the prevention of the
greenhouse effect ). There are tens, possibly hundreds of reasons why a
system won't go standby as its meant to. MST is using several techniques to
work around a lot of them...

The cumulative environmental effect of more abstemious use of electrical
power by millions of computer users around the world could be significant.
I hope Microsoft will pay more attention to the operation of these power
management features now. I think Microsoft has a responsibility to improve
this functionality, due to its importance for the welfare of the natural
environment. We can all help if Microsoft gives us reliable settings which
we can use.

Jeff Hook

 

[Leonard Grey]

"(It seems more likely that Windows XP's Home Edition isn't using the
PSU's capability correctly.)"

lol...You have this "thing" about Windows XP. An operating system
doesn't 'use' a PSU rightly or wrongly, just like your television
doesn't 'use' the wall socket rightly or wrongly.

 

[Jeffrey L. Hook]

lol...You have this "thing" about Windows XP. An operating system doesn't
'use' a PSU rightly or wrongly, just like your television doesn't 'use'
the wall socket rightly or wrongly.

I appreciate the comment. It should be obvious that I'm ignorant both about
personal computer hardware topics and about electricity, so you're educating
me.

I thought a PSU performed some power-related "management" function. For
example, I saw many discussions of the provision by PSUs of appropriate
amounts of current/voltage ("whatever") to various system components via
multiple PSU "rails." Then I was confused to see that PC Power & Cooling
advocated single-rail design, arguing that multiple "rails" were obsolete.

The talk about "rails" and about the provision of various amounts and types
of power to various system components suggested that the PSU was managing or
controlling the distribution of power in response to simultaneous "demands"
by different components, which needed different voltage and amperage, etc.
I saw a small printed circuit board (PCB) inside my original PSU and in
"cover-off" photos of other PSUs. That suggested the PSU had some
computational/logic capability. For example, I assumed the PSU would need
to "shift" output from rail to rail. (However, the separate "rails" may
simply always be "flowing" with current at varying numbers of volts and of
amperes.)

The Windows XP Home "Power Options Properties" settings suggested some type
of similar power management or regulation function by the OS.

I should educate myself about these topics by conducting my own on-line
research, not by discussing them here. My ignorance of this stuff is so
extreme that an educational discussion here would be too basic to be of
interest to anyone, and it would detract from the value of this thread.

However, isn't the purpose of the "Power Options Properties" settings to
allow the user to adjust the OS's "use" of system power whether the system's
powered by a battery or by DC output of a desktop PSU? (My "thing" about
Windows XP may result from my reluctance to consider that my brand-new PC
Power & Cooling PSU may simply *not* be working correctly, "right out of the
retail box." I was thinking that, "Of course my brand new PSU couldn't be
malfunctioning; the problem must be caused by the OS." More about those
details in the separate upcoming thread about my system problems.)

Jeff Hook

 

[Leonard Grey]

"...isn't the purpose of the "Power Options Properties" settings to
allow the user to adjust the OS's "use" of system power..."

It allows you to choose how many minutes of inactivity there should be
before Windows sends a command to the hardware to power down. How the
hardware reacts to the command is not controlled by Windows. The Power
Options is also where you enable hibernation and configure your UPS
software.

 

[Bill Sharpe]

Can anyone either explain the confusing settings in Windows XP's Power
Options Properties dialogue, or refer me to an intelligible on-line
explanation? The Power Options dialogue's found in Control Panel. It can
also be reached via the "Power" button on the "Screen Saver" tab in the
Desktop's Display Properties dialogue. (I'm running XP's Home Edition with
SP2.)

The Power Options Properties "Power Schemes" tab lists four settings:

1. monitor off,
2. hard drive off,
3. system standby, and
4. system hibernation.

The "Power Schemes" contextual help feature provides two separate "tool tip"
explanatory texts for each of those four settings. Click the help cursor on
the "label" for any of the settings, at the left side of the "page," and
you'll be shown an explanation which makes no distinction between portable
and desktop systems. Click the help cursor on that same setting's "field"
itself, at the right side of the "page," and the help text will explain that
the setting is used when the system is "running on AC power," which suggests
the setting's relevant only to battery-powered systems.

I don't understand the relationship of the time intervals for hard drive
shut-down, for system standby, and for system hibernation. I'm assuming a
system can't enter standby or hibernation if its hard drive has already been
powered-down first. Can a drive which has been powered-down be "repowered"
in order to put the system into standby or hibernation? How can a system's
state be preserved (with respect to programs which were running and with
respect to folders and files which were open) if a drive shuts down *before*
the system enters standby or hibernation?

Thanks.

Jeff Hook, NJ, USA
(I've cross-posted this message to the Windows XP Hardware group, to the
Windows XP Help & Support group, and to the Windows XP Performance &
Maintenance group.)

I think you'll get the maximum power saving if you just turn the
computer off when you are finished using it and not worry about various
power schemes.

I realize this isn't the question you asked in the subject line, which
others have addressed in great detail.

Bill

 

[Jeffrey L. Hook]

I think you'll get the maximum power saving if you just turn the computer
off when you are finished using it and not worry about various power
schemes.

I don't know much about hardware but I think you're probably right.

However, "turning the computer off" isn't desirable for users who benefit
from finding the system in a "helpful state" when they return to it.

Consider my case. I'm not a power user, but I've been an avid personal
computer user for nine years. I make heavy use of the few functions which I
do use. I have a gigantic data directory of almost 80,000 files in more
than 35,000 folders and I add to this directory constantly. Many of those
80K files are only short cuts to executables, and many others are empty
files, waiting to "collect" content, but most of them contain content which
I'm continually revising and supplementing and studying and
cross-referencing, etc. I find it's helpful view of my complex, branched
data directory "tree" in the Folder Pane of Windows Explorer in the "Windows
Classic View," but my directory's so large that I have five Windows Explorer
application windows open at all times, "stacked" on my Task Bar. Each of
those windows "zooms in" on one of the sub-sections of my data directory
where I'm most often working. I do all of my local navigation in Windows
Explorer. Sub-sections of each of the five Windows Explorer views of my
overall data directory are "expanded" and aren't "collapsed," so I can
easily re-navigate to various folders which are out on the peripheries of
various "branches" of my "tree." I often "juggle" multiple files which I've
created for different aspects of the same topics, and it's helpful to allow
those files to remain open, "stacked" in a group on the Task Bar, for my
simple word processor, Works 7.0. That limited application is good enough
for my purposes and it doesn't require me to learn functions which I don't
need.

I've found that it's useful to create "sample" files in my word processor.
I format them for various types of data and for various purposes, such as
"Journals," "Research," "News," etc. I've built up a large directory of
such sample files and I've also created sub-directories of multiple sample
files in multiple folders. When I wish to create a new directory about a
new topic, I can copy an entire sub-directory of various files and folders
from my sample directory, and paste it into a new location in my data
directory, where I can begin to fill in on-line texts, images, my own
records of my own activity, etc.

My use of personal computing technology is "intensive," but it's limited to
basic word processing, Web research, and E-mail, and I'm sure it can't begin
to compare with much greater use which is made by other users who are far
more capable than I am.

I think that any intensive personal computer use is facilitated by Windows'
ability to enter various "sleep" states from which Windows systems can
restore their prior states. In effect, I benefit from "leaving work on my
desk overnight," and from leaving "pending" work "on my desk" during the
day, and I believe that rebooting the system would clear away all of those
open folders and files and application windows. Am I incorrect about that?
If I could power the system down entirely but restore it to its prior state,
with respect to open application windows, folders, and files, then I'd wish
to use that means of reducing power consumption, but I don't think that can
be done... yet.

I think personal computing technology is a spectacular boon, and I hope to
continue to make greater use of it. I'm also concerned about the welfare of
the natural environment and about the damage which human activity has done
to the global ecosystem. I believe that system "sleep states" can allow us
to reduce our consumption of electricity (and the associated power plant
emissions) while we continue to use this technology.

Jeff Hook, NJ, USA

 

[JohnO]

In effect, I benefit from "leaving work on my

desk overnight," and from leaving "pending" work "on my desk" during the
day, and I believe that rebooting the system would clear away all of those
open folders and files and application windows. Am I incorrect about
that?
No.

If I could power the system down entirely but restore it to its prior
state,
with respect to open application windows, folders, and files, then I'd
wish
to use that means of reducing power consumption, but I don't think that
can
be done... yet.

Yes, it can. Hibernation is the answer. During hibernation power consumption
is ~zero, or the same as if your PC is off. Shutdown and restart are maybe
20 seconds each, and your desktop is exactly as you left it. It requires
hard drive space equal to the amount of RAM in your system. I've used it for
many years on this laptop, leaving docs open for many days as I work on them
at home and in the office. I can leave the laptop in my bag for an entire
weekend, and fire it up on Monday and everything is just like it was Friday,
including a full battery.

Check Windows Help for all the configuration details (it's *very* simple).
If you have questions, come on back. (posted from the hardware group)

-John O

 

[Jeffrey L. Hook]

Thanks, John. I'm glad you advocate hibernation. I hope users are
concerned about the environmental effects of the production of most of the
electricity which we use to power our desktop systems and which we also use
to charge our portable systems' batteries. I've used standby and
hibernation for years. I hadn't been required to look again at Windows XP
Home's "Power Schemes" settings until my system became unable to return to
its prior state from standby after I replaced its power supply unit. I
found the "Power Schemes" settings confusing and I began this thread to
request clarification.

I wanted to reply to Bill Sharpe's suggestion that shutting a system down
was the best way to conserve power (and, indirectly, to reduce power plant
emissions, etc.) I wanted to speak up for environmental stewardship and I
also wanted to state that the complete shut down of a system isn't desirable
if it entails the "closing" of open items which created the "helpful"
details of the system's prior state. I know so little about hardware that I
had to admit I didn't know if it's possible to restore a system's prior
state after the system had been fully shut down.

Leonard Grey referred to this good Fred Langa Information Week article about
the five "official" system sleep/power consumption states:

http://www.informationweek.com/story/IWK20020927S0028


I'll read that text tonight so I can reply to the suggestions about changing
sleep state settings in the BIOS which were made in reference to those
"official" sleep states this morning by "Bob I" in my other thread in these
groups: "Win XP Home Won't Resume from Standby, Reboots Instead."

I wanted this thread to focus only on the Windows XP Home "Power Options
Properties" "Power Scheme" settings, and on the overall topics of "sleep
states" and of system power management. I don't want to "cross" these two
threads.

Jeff Hook, NJ, USA

...Hibernation is the answer. During hibernation power consumption

is ~zero, or the same as if your PC is off. Shutdown and restart are maybe
20 seconds each, and your desktop is exactly as you left it. It requires
hard drive space equal to the amount of RAM in your system. I've used it for
many years on this laptop, leaving docs open for many days as I work on them
at home and in the office. I can leave the laptop in my bag for an entire
weekend, and fire it up on Monday and everything is just like it was Friday,
including a full battery.

Check Windows Help for all the configuration details (it's *very* simple).
If you have questions, come on back. (posted from the hardware group)

-John O

 

[Jeffrey L. Hook]

Thanks to everybody who replied to my recent inquiry in this thread.

I read the excellent Fred Langa Information Week Magazine article about
"Sleep States" which Leonard Grey submitted in my first thread. It's "To
Sleep, Perchance To Hibernate..." at:

http://www.informationweek.com/story/IWK20020927S0028


It was published on 9-30-02, but I assume it's still relevant. (I assume
it's relevant to my system, which was assembled by Gateway on 12-24-02. If
anyone wishes to comment about the possibility that my *new* PC Power &
Cooling PSU may have "conflicted" with the components of my *12-24-02*
system unit with respect to system sleep states, please do. You might
prefer to add your remarks to my separate "Win XP Home Won't Resume" thread
in these groups, rather than here. I hoped this thread would focus on the
basics of system power management.)

Fred provides a comprehensive but succinct explanation of all system sleep
states, from "S0" through "S5." I highly recommend his text to any other PC
user who lacks hardware knowledge.

Fred offers links to the Advanced Configuration and Power Interface
Consortium, at:

http://www.acpi.info/index.html


to Microsoft's ACPI pages, at:

http://www.microsoft.com/whdc/default.mspx


and to Intel's ACPI pages, at:

http://www.intel.com/technology/iapc/acpi/


He also provides some old Google Web search-response sets which still look
good now.

Thanks again, Leonard, for posting Fred Langa's text.

I'm now assuming that the supposed problem which I discussed in my separate
thread in these groups may *not* be a problem at all. Please check that
thread if you'd like to contribute to a discussion of the details of sleep
states in my own system. It's "Win XP Home Won't Resume from Standby,
Reboots Instead."

Jeff Hook, NJ, USA