diff -r 9cdbe1d8d12a -r 129a9a1d514f Hardware/ATI/ATIGPU.cs
--- a/Hardware/ATI/ATIGPU.cs	Tue Mar 09 22:27:10 2010 +0000
+++ b/Hardware/ATI/ATIGPU.cs	Wed Mar 10 17:56:08 2010 +0000
@@ -123,13 +123,22 @@
       if (ADL.ADL_Overdrive5_CurrentActivity_Get(adapterIndex, ref adlp)
         == ADL.ADL_OK) 
       {
-        coreClock.Value = 0.01f * adlp.EngineClock;
-        memoryClock.Value = 0.01f * adlp.MemoryClock;
-        coreVoltage.Value = 0.001f * adlp.Vddc;
-        coreLoad.Value = adlp.ActivityPercent;
-        ActivateSensor(coreClock);
-        ActivateSensor(memoryClock);
-        ActivateSensor(coreVoltage);
+        if (adlp.EngineClock > 0) {
+          coreClock.Value = 0.01f * adlp.EngineClock;
+          ActivateSensor(coreClock);
+        }
+
+        if (adlp.MemoryClock > 0) {
+          memoryClock.Value = 0.01f * adlp.MemoryClock;
+          ActivateSensor(memoryClock);
+        }
+
+        if (adlp.Vddc > 0) {
+          coreVoltage.Value = 0.001f * adlp.Vddc;
+          ActivateSensor(coreVoltage);
+        }
+
+        coreLoad.Value = adlp.ActivityPercent;                        
         ActivateSensor(coreLoad);
       } else {
         DeactivateSensor(coreClock);