Add VRAM memory and bandwidth sensors for Intel discrete GPUs

- Add GPU Memory Total, Used, Free sensors (SmallData type, in MB)
- Add GPU Memory load sensor (percentage)
- Add GPU Memory Read/Write bandwidth sensors (Throughput type, in B/s)
- Use D3DDisplayDevice API to query VRAM usage via Windows kernel
- Match Intel discrete GPUs using PCI vendor/device IDs
- Include fallback detection for Intel GPUs if initial matching fails
- Bandwidth sensors read from Intel GCL telemetry with unit conversion

Author: sergiye

OpenHardwareMonitorLib/Hardware/Gpu/IntelDiscreteGpu.cs

@@ -33,9 +33,20 @@ internal sealed class IntelDiscreteGpu : GenericGpu
     private readonly Sensor _voltageCore;
     private readonly Sensor _voltageMemory;
 
+    // Memory sensors
+    private readonly Sensor _memoryFree;
+    private readonly Sensor _memoryTotal;
+    private readonly Sensor _memoryUsed;
+    private readonly Sensor _memoryLoad;
+
+    // Bandwidth sensors
+    private readonly Sensor _memoryBandwidthRead;
+    private readonly Sensor _memoryBandwidthWrite;
+
     // Timestamps
     private double _currentTimestamp = double.NaN;
     private string _deviceId;
+    private string _d3dDeviceId;
 
     // Intel GCL properties and data
     private readonly IntelGcl.ctl_device_adapter_handle_t _handle;
@@ -49,6 +60,8 @@ internal sealed class IntelDiscreteGpu : GenericGpu
     private double _lastRenderComputeActivityCounter = double.NaN;
     private double _lastTimestamp = double.NaN;
     private double _lastTotalCardEnergyReading = double.NaN;
+    private double _lastVramReadBandwidthCounter = double.NaN;
+    private double _lastVramWriteBandwidthCounter = double.NaN;
     private IntelGcl.ctl_device_adapter_properties_t _properties;
 
     // Telemetry data
@@ -64,6 +77,9 @@ public IntelDiscreteGpu(IntelGcl.ctl_device_adapter_handle_t handle, ISettings s
         if (!InitializeDevice())
             return;
 
+        // Try to get D3D device identifier for memory monitoring
+        _d3dDeviceId = GetD3DDeviceId();
+
         // Initialize temperature sensors
         _temperatureGpuCore = new Sensor("GPU Core", 0, SensorType.Temperature, this, settings);
         _temperatureMemory = new Sensor("GPU Memory", 1, SensorType.Temperature, this, settings);
@@ -85,6 +101,16 @@ public IntelDiscreteGpu(IntelGcl.ctl_device_adapter_handle_t handle, ISettings s
         _loadRenderCompute = new Sensor("GPU Render/Compute", 1, SensorType.Load, this, settings);
         _loadMedia = new Sensor("GPU Media", 2, SensorType.Load, this, settings);
 
+        // Initialize memory sensors
+        _memoryFree = new Sensor("GPU Memory Free", 0, SensorType.SmallData, this, settings);
+        _memoryUsed = new Sensor("GPU Memory Used", 1, SensorType.SmallData, this, settings);
+        _memoryTotal = new Sensor("GPU Memory Total", 2, SensorType.SmallData, this, settings);
+        _memoryLoad = new Sensor("GPU Memory", 3, SensorType.Load, this, settings);
+
+        // Initialize bandwidth sensors
+        _memoryBandwidthRead = new Sensor("GPU Memory Read", 0, SensorType.Throughput, this, settings);
+        _memoryBandwidthWrite = new Sensor("GPU Memory Write", 1, SensorType.Throughput, this, settings);
+
         // Initialize fan sensors based on available fans
         int fanCount = (int)GetFanCount();
         _fans = new Sensor[fanCount];
@@ -159,6 +185,34 @@ private bool InitializeDevice()
         return false;
     }
 
+    private string GetD3DDeviceId()
+    {
+        // Try to find matching D3D device using PCI device ID
+        string[] deviceIdentifiers = D3DDisplayDevice.GetDeviceIdentifiers();
+        if (deviceIdentifiers == null || deviceIdentifiers.Length == 0)
+            return null;
+
+        // Intel vendor ID is 0x8086
+        string vendorPattern = $"VEN_{_properties.pci_vendor_id:X}";
+        string devicePattern = $"DEV_{_properties.pci_device_id:X}";
+
+        foreach (string deviceIdentifier in deviceIdentifiers)
+        {
+            // Check if this device matches Intel vendor and device IDs
+            if (deviceIdentifier.IndexOf(vendorPattern, StringComparison.OrdinalIgnoreCase) != -1 &&
+                deviceIdentifier.IndexOf(devicePattern, StringComparison.OrdinalIgnoreCase) != -1)
+            {
+                // Verify it's a valid D3D device by trying to get device info
+                if (D3DDisplayDevice.GetDeviceInfoByIdentifier(deviceIdentifier, out D3DDisplayDevice.D3DDeviceInfo deviceInfo))
+                {
+                    return deviceIdentifier;
+                }
+            }
+        }
+
+        return null;
+    }
+
     public override void Update()
     {
         if (!IsValid)
@@ -191,6 +245,19 @@ public override void Update()
             UpdateUtilizationFromActivityCounter(_telemetry.renderComputeActivityCounter, ref _lastRenderComputeActivityCounter, _loadRenderCompute);
             UpdateUtilizationFromActivityCounter(_telemetry.mediaActivityCounter, ref _lastMediaActivityCounter, _loadMedia);
 
+            // Try to get D3D device ID if we haven't found it yet
+            if (string.IsNullOrEmpty(_d3dDeviceId))
+            {
+                _d3dDeviceId = GetD3DDeviceId();
+            }
+
+            // Update VRAM memory sensors (using D3D API)
+            UpdateMemorySensors();
+
+            // Update VRAM bandwidth sensors
+            UpdateBandwidthFromCounter(_telemetry.vramReadBandwidth, ref _lastVramReadBandwidthCounter, _memoryBandwidthRead);
+            UpdateBandwidthFromCounter(_telemetry.vramWriteBandwidth, ref _lastVramWriteBandwidthCounter, _memoryBandwidthWrite);
+
             // Update fan sensors
             UpdateFanSpeeds(_fans);
         }
@@ -420,4 +487,97 @@ private void UpdateUtilizationFromActivityCounter(IntelGcl.ctl_oc_telemetry_item
 
         lastActivityReading = currentActivity;
     }
+
+    private void UpdateMemorySensors()
+    {
+        if (string.IsNullOrEmpty(_d3dDeviceId))
+        {
+            // Fallback: Try to find any Intel discrete GPU
+            string[] deviceIdentifiers = D3DDisplayDevice.GetDeviceIdentifiers();
+            if (deviceIdentifiers != null)
+            {
+                foreach (string deviceId in deviceIdentifiers)
+                {
+                    if (deviceId.IndexOf("VEN_8086", StringComparison.OrdinalIgnoreCase) != -1)
+                    {
+                        if (D3DDisplayDevice.GetDeviceInfoByIdentifier(deviceId, out D3DDisplayDevice.D3DDeviceInfo testInfo))
+                        {
+                            if (testInfo.GpuDedicatedLimit > 0 && !testInfo.Integrated)
+                            {
+                                _d3dDeviceId = deviceId;
+                                break;
+                            }
+                        }
+                    }
+                }
+            }
+
+            if (string.IsNullOrEmpty(_d3dDeviceId))
+                return;
+        }
+
+        if (D3DDisplayDevice.GetDeviceInfoByIdentifier(_d3dDeviceId, out D3DDisplayDevice.D3DDeviceInfo deviceInfo))
+        {
+            // Get dedicated video memory (VRAM) usage
+            ulong totalBytes = deviceInfo.GpuDedicatedLimit;
+            ulong usedBytes = deviceInfo.GpuDedicatedUsed;
+            ulong freeBytes = totalBytes > usedBytes ? totalBytes - usedBytes : 0;
+
+            if (totalBytes > 0)
+            {
+                // Convert bytes to MB for display
+                _memoryTotal.Value = totalBytes / (1024.0f * 1024.0f);
+                ActivateSensor(_memoryTotal);
+
+                _memoryUsed.Value = usedBytes / (1024.0f * 1024.0f);
+                ActivateSensor(_memoryUsed);
+
+                _memoryFree.Value = freeBytes / (1024.0f * 1024.0f);
+                ActivateSensor(_memoryFree);
+
+                // Calculate load percentage
+                _memoryLoad.Value = (float)((double)usedBytes / totalBytes * 100.0);
+                ActivateSensor(_memoryLoad);
+            }
+        }
+    }
+
+    private void UpdateBandwidthFromCounter(IntelGcl.ctl_oc_telemetry_item_t bandwidthItem, ref double lastBandwidthReading, Sensor bandwidthSensor)
+    {
+        if (!IsValid || bandwidthSensor == null)
+            return;
+
+        // If the telemetry item directly provides bandwidth value (not a counter)
+        if (bandwidthItem.bSupported)
+        {
+            double bandwidthValue = GetTelemetryValue(bandwidthItem);
+            
+            if (!double.IsNaN(bandwidthValue) && bandwidthValue >= 0)
+            {
+                // Bandwidth is typically in GB/s or MB/s, convert to B/s for Throughput sensor
+                // Check the units to determine if conversion is needed
+                if (bandwidthItem.units == IntelGcl.ctl_units_t.CTL_UNITS_BANDWIDTH_MBPS)
+                {
+                    // Convert MB/s to B/s (multiply by 1024*1024)
+                    bandwidthValue = bandwidthValue * 1024.0 * 1024.0;
+                }
+                else if (bandwidthItem.units == IntelGcl.ctl_units_t.CTL_UNITS_MEM_SPEED_GBPS)
+                {
+                    // Convert GB/s to B/s (multiply by 1024*1024*1024)
+                    bandwidthValue = bandwidthValue * 1024.0 * 1024.0 * 1024.0;
+                }
+
+                bandwidthSensor.Value = (float)bandwidthValue;
+                ActivateSensor(bandwidthSensor);
+            }
+            else
+            {
+                bandwidthSensor.Value = null;
+            }
+        }
+        else
+        {
+            bandwidthSensor.Value = null;
+        }
+    }
 }