How can I read the GPU load?

Question

I am writing a program that monitors various resources of the computer, such as CPU usage and so on. I want to monitor GPU usage (the GPU load, not temperature) as well.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;
using DannyGeneral;


namespace CpuUsage
{
    public partial class Form1 : Form
    {
        private bool processEnded;
        private Process[] processList;
        private string timeStarted;
        private string timeEnded;
        private List<float> processValues;
        private bool alreadyRun;
        private DateTime dt;
        private DateTime dt1;
        private PerformanceCounter theCPUCounter;
        private PerformanceCounter theMemCounter;
        private PerformanceCounter specProcessCPUCounter;
        private float cpuUsage;
        private float memUsage;
        private List<float> Values;

        public Form1()
        {
            InitializeComponent();

            processEnded = false;
            processList = Process.GetProcesses();
            for (int i = 0; i < processList.Count(); i++)
            {
                listView1.Items.Add(processList[i].ProcessName);
            }
            processValues = new List<float>();
            alreadyRun = false;
            dt = DateTime.Now;


            Values = new List<float>();
                theCPUCounter = new PerformanceCounter("Processor", "% Processor Time", "_Total");
                theMemCounter = new PerformanceCounter("Memory", "Available MBytes");
                specProcessCPUCounter = new PerformanceCounter("Process", "% Processor Time", Process.GetCurrentProcess().ProcessName);

                Logger.Write("The Program Started At ***   " + DateTime.Now.ToShortTimeString());

        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void timer1_Tick(object sender, EventArgs e)
        {
            memUsage = theMemCounter.NextValue();
            label1.Text = memUsage.ToString();
            Logger.Write("Memory Usage   " + memUsage.ToString());
            cpuUsage = this.theCPUCounter.NextValue();
            label2.Text = cpuUsage.ToString();
            Logger.Write("Cpu Usage   " + this.cpuUsage.ToString());
            Values.Add(cpuUsage);
            isProcessRunning();
            if (alreadyRun == true)
            {
                processValues.Add(cpuUsage);
            }

        }

Answer 1

The video card's own CPU is called a GPU.

Look for performance counters related to that or video (using Start->Run->PerfMon or typing PerfMon in the Start menu's search box; right-click on the graph and choose Add Counter...).

If your video card maker didn't provide any performance counters for the GPU, there aren't any for you to get.