---
title: "Should you disable HPET for gaming? What the HPET device and useplatformclock do"
description: "HPET is a hardware timer on the motherboard. What the tweak changes, when it helps, when it hurts and how to undo it."
url: https://frozentweaks.com/tweaks/disable-hpet
author: Frost LIVE, Founder of Frozen Tweaks
published: 2026-10-08
updated: 2026-10-08
category: "CPU"
source: Frozen Tweaks (https://frozentweaks.com)
---

# Should you disable HPET for gaming? What the HPET device and useplatformclock do

**Short answer:** HPET is a hardware timer on the motherboard. Windows normally keeps time with the processor's own counter (TSC) and uses HPET only when told to. This tweak disables the HPET device driver in Windows, so the system cannot fall back to it. In the registry it sets Start to 4 under HKLM\SYSTEM\CurrentControlSet\Services\hpet.

## In the app

- Switch: Disable HPET Device (CPU, Pro, Advanced)
- Undo: Yes. Switching it off sets a standard Windows value, which may not be exactly how you had it.
- Catalog row: https://frozentweaks.com/tweaks#t-1109

## What it does

HPET is a hardware timer on the motherboard. Windows normally keeps time with the processor's own counter (TSC) and uses HPET only when told to. This tweak disables the HPET device driver in Windows, so the system cannot fall back to it.

In the app the switch is called "Disable HPET Device", described there as: Disables HPET driver to favor TSC/HPET-free timing path (reboot).

## When it helps

- Systems where HPET was forced on (bcdedit useplatformclock true), which makes timer calls slower and can lower frame rates.

## When it hurts

- On a default Windows install HPET is not the active clock, so disabling the device usually changes nothing.
- A few systems and tools expect the device to exist. If timing or audio behaves oddly afterwards, switch it back.

## 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\Services\hpet` | `Start` | `4` | 3 |

Source: Tweaks/hpet_device_off.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\Services\hpet" /v "Start" /t REG_DWORD /d 4 /f
```

Put it back:

```bat
reg add "HKLM\SYSTEM\CurrentControlSet\Services\hpet" /v "Start" /t REG_DWORD /d 3 /f
```

See what it is set to now:

```bat
reg query "HKLM\SYSTEM\CurrentControlSet\Services\hpet" /v "Start"
```

## How to undo it

Switch the tweak off in Frozen Tweaks. It writes Start back to 3.

## Verdict

The useful part is making sure useplatformclock is not set. Disabling the device on top is mostly belt and braces.

## Questions

### What does the "Disable HPET Device" tweak change in Windows?

In the registry it sets Start to 4 under HKLM\SYSTEM\CurrentControlSet\Services\hpet.

### What is the standard value of Start?

Frozen Tweaks writes 3 when you switch the tweak off, which is the value it treats as the Windows standard. With the tweak on, Start is 4.

### Is "Disable HPET Device" safe to switch on?

The useful part is making sure useplatformclock is not set. Disabling the device on top is mostly belt and braces. The main cost: On a default Windows install HPET is not the active clock, so disabling the device usually changes nothing.

### How do I undo it?

Switch the tweak off in Frozen Tweaks. Switching it off sets a standard Windows value, which may not be exactly how you had it.

### Does it need a restart?

Yes, the change applies after a restart.

### Is "Disable HPET Device" free in Frozen Tweaks?

It is part of Frozen Pro and Elite. You can also make the change by hand with the values on this page.

## Related guides

- [How to Reduce Input Lag on PC: The Whole Latency Chain](https://frozentweaks.com/guides/reduce-input-lag)

## More tweak explainers

- [Power throttling](https://frozentweaks.com/tweaks/disable-power-throttling)
- [CPU core parking](https://frozentweaks.com/tweaks/disable-core-parking)
- [Dynamic tick and HPET](https://frozentweaks.com/tweaks/disable-dynamic-tick)

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