The helper is optional. Most users should start with just the Stream Deck plugin and decide later. macOS users do not need the helper at all — it is Windows-only.
Without the helper, the plugin can already show CPU, memory, disk and network usage, and on NVIDIA cards: GPU usage, temperature, power, and voltage. That covers most Stream Deck keys people set up first.
Install the helper if you want
Depending on your hardware, the helper can also expose:
- CPU package temperature and power
- motherboard sensors, fan speed, voltage readings
- detailed GPU sensors, especially on non-NVIDIA cards
- other low-level data exposed by LibreHardwareMonitor
The exact list depends on your machine — different CPUs, GPUs, motherboards, and sensor chips expose different data, and not every machine reports every sensor. You can install the helper later; you do not need to decide during your first setup.
Why a driver is involved
Windows does not expose these deeper sensors through standard user-mode APIs. Reading them requires a kernel driver. Many Windows system tools use drivers for similar reasons, including antivirus tools, game anti-cheat systems, RGB and fan-control utilities, and hardware-monitoring apps.
Installing any driver is still something to do deliberately. The rest of this page explains what gets installed and what each part does.
What gets installed
The helper sensor stack has two pieces:
- the ShoMetrics Windows helper, a local Windows service that runs in the background
- the third-party PawnIO driver, used by LibreHardwareMonitor inside the helper for low-level sensor access
ShoMetrics does not require you to install LibreHardwareMonitor separately — the helper uses the library directly.
If you do not already have PawnIO installed, the helper installer installs it for you — you will be asked to accept PawnIO’s own agreement during that step.
If PawnIO is already installed, the helper installer leaves it as is and does not reinstall it. To reinstall or update PawnIO, you can do that yourself from pawnio.eu.
You can also choose not to install PawnIO. The helper still runs, but most of the sensors it can provide will be unavailable without the driver.
This step is install-only: removing ShoMetrics later does not remove PawnIO — you need to uninstall PawnIO yourself (see What PawnIO is below).
What PawnIO is
PawnIO is a small, signed Windows driver that hardware tools use to read sensors Windows otherwise keeps locked away. The part that matters for trust: it only lets a fixed set of signed modules it trusts reach your hardware — never arbitrary apps or arbitrary code.
PawnIO is third-party software, and removing ShoMetrics does not remove it — if you would like PawnIO gone, you will need to uninstall it yourself from Windows Settings → Installed apps. ShoMetrics deliberately leaves it in place because other popular tools use PawnIO too (for example OpenRGB and some Lian Li case-lighting sync apps), and silently pulling a shared driver could break them in surprising ways. If you are not sure whether anything else relies on it, a safe check is to uninstall PawnIO and watch for anything breaking — if nothing does, you are all set.
Some strict anti-cheat systems, such as FACEIT, have previously misreported PawnIO. According to the PawnIO author, the PawnIO.Setup issue should be fixed as of 2.1.0. We recommend installing PawnIO only from the official site, and using version 2.1.0 or newer.
If you have read complaints about LHM’s old WinRing0 driver
Older LibreHardwareMonitor versions shipped a driver called WinRing0 that
had known security concerns (CVE-2020-14979) and is what some users have
flagged on reviews of other LHM-based tools. ShoMetrics has never used
WinRing0 — the helper has been built on PawnIO from the first release.
If you do not want the driver
You can simply skip PawnIO. The Stream Deck plugin still works without the helper, and the helper still runs without PawnIO — but most of the sensors the helper can provide need driver access, so those will be unavailable.
Before installing
- download the helper from the official ShoMetrics download page or release, and download PawnIO only from pawnio.eu
- be ready to approve administrator prompts for both installers
- note that uninstalling ShoMetrics does not automatically uninstall PawnIO
Ready to install? See How do I install the Windows helper?.