Comparisons · Power model behaviour and command definitions as published in Microsoft's What is Modern Standby and Powercfg command-line options (read 2026-09-21)

A laptop that drains in your bag may be behaving as designed: Modern Standby against S3

You close the lid, put the laptop in a bag, and it comes out with less charge than you expected. That is not necessarily a worn battery. Many recent laptops do not use the traditional S3 sleep state at all; they use Modern Standby, a power model in which software runs in short controlled bursts at very low power by design. And Microsoft states plainly that switching between S3 and Modern Standby cannot be done by changing a BIOS setting, and is not supported without a complete OS reinstall. It is therefore decided when you buy the machine. This guide was written on 2026-09-21 from two Microsoft pages and gives read-only commands for finding out which one you have. No power draw was measured here.

Published 2026-09-21 · Updated 2026-09-21 · FaultNote editorial policy

A laptop that drains in your bag may be behaving as designed: Modern Standby against S3 overview: 1. Modern Standby is not designed to be stopped, 2. It cannot be changed after you buy, 3. Finding out which one you have, 4. Sorting the symptom into the right question, 5. What this guide did not measure — An overview of this guide’s steps and checks, not a screenshot of the app.

Who this guide is for and what to prepare

Laptop owners bothered by how much charge is lost while the machine is asleep
People trying to separate a machine that wakes on its own from one that is simply slow to resume
People choosing a laptop who did not know sleep behaviour differs by model

What you need

Be able to open Command Prompt or PowerShell as an administrator — every command below only reports state
Note the model number of the laptop, for looking up the maker's specification page
If you suspect the battery itself, read this site's guide to the battery health report first

1. Modern Standby is not designed to be stopped

Microsoft's What is Modern Standby states the aim: Connected Standby, and consequently Modern Standby, enable an instant on / instant off user experience, similar to smartphone power models. Just like the phone, the S0 low power idle model enables the system to stay connected to the network while in a low power mode.

A phone-like experience, staying on the network at low power. The name for it is S0 low power idle.

The same page describes what that costs: low power is reached by waking from the lowest power state only when necessary and letting software execute in short, controlled bursts. Which is to say the machine is not fully stopped. Losing a little charge in a bag follows directly from that design. This guide measured nothing, so it quotes no percentage.

On the relationship to the older state, the page says: Modern Standby allows for market segments previously limited to the Traditional Sleep (S3) power model to take advantage of the low power idle model. It adds: The number of systems supporting Modern Standby rather than S3 is increasing over time.

2. It cannot be changed after you buy

The reason this belongs among pre-purchase checks is one sentence: Switching between S3 and Modern Standby cannot be done by changing a setting in the BIOS. Switching the power model is not supported in Windows without a complete OS re-install.

Unofficial procedures for changing it circulate. Microsoft's page does not present them as supported, and this guide does not give them.

So if sleep behaviour matters to you, it is decided at purchase. Look for Modern Standby, S0ix or Connected Standby in the maker's specification, or run the command below on a machine on display.

3. Finding out which one you have

Windows can report the sleep states a machine offers. In Microsoft's list of powercfg options, /availablesleepstates, /A is described as Reports the sleep states available on the system. Run powercfg /a from an administrator Command Prompt and it lists what is available and what is not, with a reason for each.

This guide could not confirm the command's exact output strings on a Microsoft page, so it will not tell you that a particular line means Modern Standby. Read how the standby entry is worded, and whether S3 appears among the states listed as unavailable on this system.

The table lists the commands whose definitions appear on that page and which bear on sleep. All of them report; none of them changes a setting.

Scroll horizontally to see the full table →

3. Finding out which one you have
Command	Microsoft's description, summarised	What it helps separate
powercfg /availablesleepstates (/a)	Reports the sleep states available on the system	The starting point for which power model this machine uses
powercfg /lastwake	Reports information about what woke the system from the last sleep transition	Naming whatever is waking the machine
powercfg /waketimers	Enumerates active wake timers	Whether a scheduled wake has been set
powercfg /requests	Enumerates application and driver power requests	Why the machine will not sleep, or sleeps only lightly
powercfg /energy	Analyzes the system for common energy-efficiency and battery life problems	A single sweep before chasing individual causes

4. Sorting the symptom into the right question

Drains during sleep covers several different causes. The table maps what you are seeing to where to look first.

The first row is the important one: a power model is not a fault, so it is not something a repair or a replacement part resolves. Wear, on the other hand, is visible in the battery report. Keeping the two apart is what avoids spending money on the wrong thing.

Scroll horizontally to see the full table →

4. Sorting the symptom into the right question
What you are seeing	What to look at first	How to read it
A slow loss while closed and idle	powercfg /a, to identify the power model	Modern Standby is designed to keep working at very low power. Not necessarily a fault
A large loss in a short time, or a warm chassis	powercfg /requests, powercfg /energy	Points at software or a driver holding a power request open
The machine wakes on its own	powercfg /lastwake, powercfg /waketimers	Names what woke it, before you start changing settings
Shorter runtime than it used to have, even fully charged	The battery health report	That is wear, not the power model. Covered separately on this site
You want to know before buying	The maker's specification wording, or powercfg /a on a display unit	Microsoft states it cannot be switched afterwards

5. What this guide did not measure

Not power draw, not rate of loss, not resume time. What it offers is Microsoft's published account of the design, and the definitions of commands you can run on your own machine. A figure like overnight loss depends on the model, the settings and what it is connected to, so none is given here.

It also does not rank the two. Microsoft describes Modern Standby as designed for an instant-on experience with the network kept up; it does not present S3 as inferior. Which is better depends on what you want from the machine.

And it does not cover unofficial ways to change the power model, because the source states the change is not supported without a complete OS reinstall.

Limitations and requirements

The commands here only report, but some need administrator rights. Their output can include device and process names, so do not paste it into a public forum unedited.
No unofficial procedure for changing the power model is given. Microsoft states that the switch cannot be made from the BIOS and is not supported without a complete OS reinstall.
The wording quoted was read on 2026-09-21. Microsoft's pages are revised.

Frequently asked questions

Is losing charge during sleep a fault?

Not necessarily. Microsoft describes Modern Standby as a design in which the system stays connected to the network at low power and software runs in short, controlled bursts. No rate of loss was measured for this guide, so no figure is given.

Can I switch to S3 in the BIOS?

Microsoft states that switching between S3 and Modern Standby cannot be done by changing a BIOS setting, and is not supported in Windows without a complete OS reinstall. This guide gives no unofficial procedure.

How do I tell which one my laptop uses?

Microsoft's powercfg documentation describes /availablesleepstates (/A) as reporting the sleep states available on the system. Run powercfg /a from an administrator Command Prompt.

My laptop wakes up on its own.

Microsoft's documentation states that /lastwake reports what woke the system from the last sleep transition and that /waketimers enumerates active wake timers. Identify the cause before changing settings.

How is this different from a worn battery?

Treat them as separate questions. The power model affects behaviour during sleep; a shorter runtime from a full charge points at wear instead. This site covers reading the battery health report separately.

Sources and verification date

Sources checked: 2026-09-21. These sources support the specifications, procedures or prices discussed here. Check each source for applicable conditions and current information.

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