diff -r 800a36a1ca8e -r dc276daadb2c Hardware/LPC/IT87XX.cs
--- a/Hardware/LPC/IT87XX.cs	Sun Feb 07 20:59:13 2010 +0000
+++ b/Hardware/LPC/IT87XX.cs	Mon Feb 08 20:18:25 2010 +0000
@@ -164,7 +164,8 @@
 
         if (value > 0) {
           sensor.Value = (value < 0xffff) ? 1.35e6f / ((value) * 2) : 0;
-          ActivateSensor(sensor);
+          if (sensor.Value > 0)
+            ActivateSensor(sensor);
         } else {
           DeactivateSensor(sensor);
         }