HardwareDevice

Introduction

HardwareDevice is an interface representing a detected hardware device (CPU or GPU) on the system. It is returned as part of the HardwareListSnapshot when you call getHardwareList(), providing identification and classification of each discovered piece of hardware.

Interface Introduction

The HardwareDevice interface describes a single hardware component discovered by LibreHardwareMonitor. You will encounter these objects inside the cpus and gpus arrays of the HardwareListSnapshot returned by getHardwareList(). Each device carries a unique identifier, a human-readable name, and metadata indicating whether it is a CPU or GPU along with its hardware type string from the underlying monitoring library.

Use IDs for Correlation

The id field is a stable identifier for a hardware device. Use it as a key when tracking device state across multiple polling cycles or when correlating hardware entries with temperature readings from getTemperature().

Properties

Property	Type	Description
id	string	Unique hardware identifier assigned by LibreHardwareMonitor
name	string	Human-readable device name (e.g., "Intel Core i7-12700K", "NVIDIA GeForce RTX 3080")
category	'cpu' | 'gpu'	Device category — always either "cpu" or "gpu"
hardwareType	string	Hardware type string from LibreHardwareMonitor describing the device class
source	'libre-hardware-monitor'	Data source identifier — always "libre-hardware-monitor"

Category Is Exhaustive

The category field is a union type limited to 'cpu' | 'gpu'. Other hardware components such as motherboards, storage drives, or memory modules are not included in the hardware list — they may appear in temperature readings but not as HardwareDevice entries.

Hardware Type String

The hardwareType value comes directly from LibreHardwareMonitor's internal type classification. It may vary across different hardware vendors and is intended for display or filtering purposes rather than strict programmatic branching. Prefer using category for CPU/GPU branching logic.

Usage

The typical workflow for working with HardwareDevice is:

1. Call getHardwareList() to retrieve the current hardware snapshot.
2. Check the isAvailable flag on the returned snapshot to confirm LibreHardwareMonitor is running.
3. Iterate over cpus and gpus arrays to access individual HardwareDevice objects.
4. Use the id to correlate devices with temperature readings or to build a device registry.

Single Device Per Category

Most consumer systems have exactly one CPU and one GPU in the hardware list. If you only need the primary CPU or GPU, access cpus[0] or gpus[0] directly after checking the array is non-empty.

Example

TypeScript

import { getHardwareList } from '@eisland/windows-performance-monitor';
import type { HardwareDevice, HardwareListSnapshot } from '@eisland/windows-performance-monitor';

// Retrieve the current hardware list snapshot
const hw: HardwareListSnapshot = getHardwareList();

// Check if LibreHardwareMonitor is available
if (hw.isAvailable) {
  // Iterate over detected CPU devices
  hw.cpus.forEach((cpu: HardwareDevice) => {
    console.log(`CPU: ${cpu.name}`);           // Log the device name
    console.log(`  ID: ${cpu.id}`);            // Log the unique identifier
    console.log(`  Type: ${cpu.hardwareType}`); // Log the hardware type string
  });

  // Iterate over detected GPU devices
  hw.gpus.forEach((gpu: HardwareDevice) => {
    console.log(`GPU: ${gpu.name}`);           // Log the device name
    console.log(`  ID: ${gpu.id}`);            // Log the unique identifier
    console.log(`  Type: ${gpu.hardwareType}`); // Log the hardware type string
  });
} else {
  // LibreHardwareMonitor is not running — hardware list is unavailable
  console.warn('Hardware list is not available.');
}

JavaScript

const { getHardwareList } = require('@eisland/windows-performance-monitor');

// Retrieve the current hardware list snapshot
const hw = getHardwareList();

// Check if LibreHardwareMonitor is available
if (hw.isAvailable) {
  // Iterate over detected CPU devices
  hw.cpus.forEach(cpu => {
    console.log(`CPU: ${cpu.name}`);           // Log the device name
    console.log(`  ID: ${cpu.id}`);            // Log the unique identifier
    console.log(`  Type: ${cpu.hardwareType}`); // Log the hardware type string
  });

  // Iterate over detected GPU devices
  hw.gpus.forEach(gpu => {
    console.log(`GPU: ${gpu.name}`);           // Log the device name
    console.log(`  ID: ${gpu.id}`);            // Log the unique identifier
    console.log(`  Type: ${gpu.hardwareType}`); // Log the hardware type string
  });
} else {
  // LibreHardwareMonitor is not running — hardware list is unavailable
  console.warn('Hardware list is not available.');
}

Notes

Snapshot vs. Live Data

HardwareDevice objects represent a snapshot of detected hardware at the time of the getHardwareList() call. The hardware list is typically stable across calls since physical devices do not change at runtime, but the snapshot may differ if LibreHardwareMonitor is started or stopped between calls.

Combining with Temperature Data

You can cross-reference HardwareDevice.id with temperature readings from getTemperature() to associate specific devices with their thermal data. This is useful for building unified hardware dashboards.

Empty Arrays

If no CPU or GPU devices are detected (for example, when LibreHardwareMonitor lacks permissions for certain device classes), the corresponding cpus or gpus array will be empty. Always check array length before accessing elements by index.

Danger Avoidance

Do Not Use Without Checking Availability

Calling getHardwareList() and immediately accessing cpus or gpus without checking isAvailable may result in empty arrays if LibreHardwareMonitor is not running. Always guard your code with an isAvailable check to avoid runtime errors from iterating over or indexing into empty arrays.

Do Not Assume Fixed Hardware Count

Do not hardcode assumptions about the number of CPUs or GPUs. Some systems may have multiple GPUs (e.g., integrated + discrete) or multiple CPU sockets. Always iterate over the arrays rather than accessing fixed indices like gpus[1].