---
title: "HiberbootEnabled 0: should you disable Fast Startup in Windows?"
description: "With Fast Startup, 'Shut down' does not fully shut down: Windows saves the kernel and drivers to disk and reloads them at the next start."
url: https://frozentweaks.com/tweaks/disable-fast-startup
author: Frost LIVE, Founder of Frozen Tweaks
published: 2026-10-08
updated: 2026-10-08
category: "Power"
source: Frozen Tweaks (https://frozentweaks.com)
---

# HiberbootEnabled 0: should you disable Fast Startup in Windows?

**Short answer:** With Fast Startup, 'Shut down' does not fully shut down: Windows saves the kernel and drivers to disk and reloads them at the next start. HiberbootEnabled set to 0 makes every shutdown a full one. In the registry it sets HiberbootEnabled to 0 under HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Power.

## In the app

- Switch: Disable Fast Startup (Power, Free, Standard)
- Undo: Yes. Switching it off puts back exactly what was there before, value for value.
- Catalog row: https://frozentweaks.com/tweaks#t-1142

## What it does

With Fast Startup, 'Shut down' does not fully shut down: Windows saves the kernel and drivers to disk and reloads them at the next start. HiberbootEnabled set to 0 makes every shutdown a full one.

In the app the switch is called "Disable Fast Startup", described there as: Makes every shutdown a full one, so driver and tweak changes always load on the next boot.

## When it helps

- Driver changes and many tweaks that only load on a real boot. It also clears problems that otherwise survive a shutdown.

## When it hurts

- Starting the PC takes a few seconds longer, mostly on hard disks. On an SSD the difference is small.

## What it writes

Read from the app's source. "Switching it off" is what the app writes when you turn the tweak off again.

Registry values:

| Key | Value | With the tweak | Switching it off |
| --- | --- | --- | --- |
| `HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Power` | `HiberbootEnabled` | `0` | Your previous value (saved before the change, or deleted if there was none). Windows default: 1 |

Source: Tweaks/pack_extra.hpp in the app's source, app 2.0.0, checked 2026-10-08.

## The same change by hand

Run in a Command Prompt opened as administrator. Make a restore point first.

```bat
reg add "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Power" /v "HiberbootEnabled" /t REG_DWORD /d 0 /f
```

Put it back:

```bat
reg add "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Power" /v "HiberbootEnabled" /t REG_DWORD /d 1 /f
```

See what it is set to now:

```bat
reg query "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Power" /v "HiberbootEnabled"
```

## How to undo it

Switch the tweak off in Frozen Tweaks. The app saved what each value was before the change and writes exactly that back, or removes the value if it did not exist.

## Verdict

Recommended on any PC with an SSD. It makes 'shut down and start again' mean what it says.

## Questions

### What does the "Disable Fast Startup" tweak change in Windows?

In the registry it sets HiberbootEnabled to 0 under HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Power.

### What is the default value of HiberbootEnabled?

The Windows default of HiberbootEnabled is 1. Frozen Tweaks sets it to 0, and switching the tweak off puts back the value you had before.

### Is "Disable Fast Startup" safe to switch on?

Recommended on any PC with an SSD. It makes 'shut down and start again' mean what it says. The main cost: Starting the PC takes a few seconds longer, mostly on hard disks. On an SSD the difference is small.

### How do I undo it?

Switch the tweak off in Frozen Tweaks. Switching it off puts back exactly what was there before, value for value.

### Is "Disable Fast Startup" free in Frozen Tweaks?

Yes. It is one of the free tweaks, with no time limit.

## Related guides

- [How to Fix Stuttering and Frame Drops: Diagnose Before You Tweak](https://frozentweaks.com/guides/fix-stuttering-frame-drops)
- [Windows 11 Gaming Optimization: What Still Works in 2026](https://frozentweaks.com/guides/windows-11-gaming-optimization)

## More tweak explainers

- [Hibernation](https://frozentweaks.com/tweaks/disable-hibernation)
- [High performance power plan](https://frozentweaks.com/tweaks/high-performance-power-plan)
- [USB selective suspend](https://frozentweaks.com/tweaks/disable-usb-selective-suspend)

---
Written by Frost LIVE, founder of Frozen Tweaks. Canonical version: https://frozentweaks.com/tweaks/disable-fast-startup