diff -r 898935080fd6 -r 5cb7eb5bf628 Hardware/LPC/W836XX.cs
--- a/Hardware/LPC/W836XX.cs	Fri Feb 19 19:50:07 2010 +0000
+++ b/Hardware/LPC/W836XX.cs	Sat Feb 20 19:51:10 2010 +0000
@@ -67,8 +67,13 @@
     private const byte VOLTAGE_BASE_REG = 0x20;
     private const byte BANK_SELECT_REGISTER = 0x4E;
     private const byte VENDOR_ID_REGISTER = 0x4F;
-    private const byte TEMPERATURE_BASE_REG = 0x50;
-    private const byte TEMPERATURE_SYS_REG = 0x27;    
+    private const byte TEMPERATURE_SOURCE_SELECT_REG = 0x49;
+
+    private string[] TEMPERATURE_NAME = 
+      new string[] {"CPU", "Auxiliary", "System"};
+    private byte[] TEMPERATURE_REG = new byte[] { 0x50, 0x50, 0x27 };
+    private byte[] TEMPERATURE_BANK = new byte[] { 1, 2, 0 };
+    private byte[] TEMPERATURE_SEL = new byte[] { 1, 2, 0 };
 
     private byte[] FAN_TACHO_REG = new byte[] { 0x28, 0x29, 0x2A, 0x3F, 0x53 };
     private byte[] FAN_TACHO_BANK = new byte[] { 0, 0, 0, 0, 5 };       
@@ -88,6 +93,17 @@
         (ushort)(address + DATA_REGISTER_OFFSET));
     } 
 
+    private void WriteByte(byte bank, byte register, byte value) {
+      WinRing0.WriteIoPortByte(
+         (ushort)(address + ADDRESS_REGISTER_OFFSET), BANK_SELECT_REGISTER);
+      WinRing0.WriteIoPortByte(
+         (ushort)(address + DATA_REGISTER_OFFSET), bank);
+      WinRing0.WriteIoPortByte(
+         (ushort)(address + ADDRESS_REGISTER_OFFSET), register);
+      WinRing0.WriteIoPortByte(
+         (ushort)(address + DATA_REGISTER_OFFSET), value); 
+    }
+   
     public W836XX(Chip chip, byte revision, ushort address) 
       : base(chip)
     {
@@ -96,10 +112,29 @@
 
       available = IsWinbondVendor();
 
-      temperatures = new Sensor[3];
-      temperatures[0] = new Sensor("CPU", 0, SensorType.Temperature, this);
-      temperatures[1] = new Sensor("Auxiliary", 1, SensorType.Temperature, this);
-      temperatures[2] = new Sensor("System", 2, SensorType.Temperature, this);
+      List<Sensor> list = new List<Sensor>();
+      switch (chip) {
+        case Chip.W83627DHG:
+          // do not add temperature sensor registers that read PECI agents
+          byte sel = ReadByte(0, TEMPERATURE_SOURCE_SELECT_REG);
+          if ((sel & 0x07) == 0)
+            list.Add(new Sensor(TEMPERATURE_NAME[0], 0,
+              SensorType.Temperature, this));
+          if ((sel & 0x70) == 0)
+            list.Add(new Sensor(TEMPERATURE_NAME[1], 1,
+              SensorType.Temperature, this));
+          list.Add(new Sensor(TEMPERATURE_NAME[2], 2,
+            SensorType.Temperature, this));
+          break;
+        default:
+          // no PECI support or extra sensor report register
+          for (int i = 0; i < TEMPERATURE_NAME.Length; i++) {
+            list.Add(new Sensor(TEMPERATURE_NAME[i], i,
+              SensorType.Temperature, this));
+          }
+          break;
+      }
+      temperatures = list.ToArray();
 
       switch (chip) {
         case Chip.W83627DHG:
@@ -145,6 +180,7 @@
     }
 
     public void Update() {
+
       foreach (Sensor sensor in voltages) {
         if (sensor.Index < 7) {
           int value = ReadByte(0, (byte)(VOLTAGE_BASE_REG + sensor.Index));
@@ -157,7 +193,7 @@
           // Battery voltage
           bool valid = (ReadByte(0, 0x5D) & 0x01) > 0;
           if (valid) {
-            sensor.Value = 
+            sensor.Value =
               0.008f * voltageGains[sensor.Index] * ReadByte(5, 0x51);
             ActivateSensor(sensor);
           } else
@@ -167,18 +203,32 @@
 
       foreach (Sensor sensor in temperatures) {
         int value;
-        if (sensor.Index < 2) {
-          value = (sbyte)ReadByte((byte)(sensor.Index + 1), TEMPERATURE_BASE_REG);
-          value = (value << 1) | ReadByte((byte)(sensor.Index + 1),
-            (byte)(TEMPERATURE_BASE_REG + 1)) >> 7;
+        switch (chip) {
+          case Chip.W83667HG:
+          case Chip.W83667HGB:
+            WriteByte(0, 0x7D, TEMPERATURE_SEL[sensor.Index]);
+            value = ((sbyte)ReadByte(0, 0x7E)) << 1;
+            break;
+          case Chip.W83627DHGP:
+            WriteByte(0, 0x7C, TEMPERATURE_SEL[sensor.Index]);
+            value = ((sbyte)ReadByte(0, 0x7D)) << 1;
+            break;
+          default:
+            value = ((sbyte)ReadByte(TEMPERATURE_BANK[sensor.Index],
+              TEMPERATURE_REG[sensor.Index])) << 1;
+            if (TEMPERATURE_BANK[sensor.Index] > 0) {
+              value |= ReadByte(TEMPERATURE_BANK[sensor.Index],
+                (byte)(TEMPERATURE_REG[sensor.Index] + 1)) >> 7;
+            }            
+            break;
+        }
+        float temperature = value / 2.0f;
+        if (temperature <= 125 && temperature >= -55) {
+          sensor.Value = temperature;
+          ActivateSensor(sensor);
         } else {
-          value = (sbyte)ReadByte(0, TEMPERATURE_SYS_REG) << 1;
+          DeactivateSensor(sensor);
         }
-        sensor.Value = value / 2.0f;
-        if (value < 0xFE)
-          ActivateSensor(sensor);
-        else
-          DeactivateSensor(sensor);
       }
 
       long bits = 0;
@@ -212,7 +262,7 @@
       r.AppendLine();
       r.AppendLine("      00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F");
       r.AppendLine();
-      for (int i = 0; i < 0x7; i++) {
+      for (int i = 0; i <= 0x7; i++) {
         r.Append(" "); r.Append((i << 4).ToString("X2")); r.Append("  ");
         for (int j = 0; j <= 0xF; j++) {
           r.Append(" ");