diff --git a/CHANGES b/CHANGES
index d9327b37..b11f1591 100644
--- a/CHANGES
+++ b/CHANGES
@@ -18,6 +18,7 @@ ask CVS about it:
 -----------------------------------------------------------------------------
 
 2.6.5 (2002????)
+  Library: Fix fan3_div writes for w8378* and it87
   Module dmi_scan: new
   Module i2c-piix4: Refuse to load on IBM systems
   Module lm92: Fix in-kernel initialization
diff --git a/lib/chips.c b/lib/chips.c
index b245ef86..43f2495e 100644
--- a/lib/chips.c
+++ b/lib/chips.c
@@ -749,7 +749,7 @@ static sensors_chip_feature w83781d_features[] =
                          SENSORS_NO_MAPPING, SENSORS_MODE_RW, 
                          W83781D_SYSCTL_FAN_DIV, VALUE(2), 0 },
     { SENSORS_W83781D_FAN3_DIV, "fan3_div", SENSORS_W83781D_FAN3, 
-                         SENSORS_NO_MAPPING, SENSORS_MODE_R, 
+                         SENSORS_NO_MAPPING, SENSORS_MODE_RW, 
                          W83781D_SYSCTL_FAN_DIV, VALUE(3), 0 },
     { SENSORS_W83781D_ALARMS, "alarms", SENSORS_NO_MAPPING, SENSORS_NO_MAPPING, 
                          SENSORS_MODE_R, W83781D_SYSCTL_ALARMS, VALUE(1), 0 },
@@ -887,7 +887,7 @@ static sensors_chip_feature as99127f_features[] =
                          SENSORS_NO_MAPPING, SENSORS_MODE_RW, 
                          W83781D_SYSCTL_FAN_DIV, VALUE(2), 0 },
     { SENSORS_W83782D_FAN3_DIV, "fan3_div", SENSORS_W83781D_FAN3, 
-                         SENSORS_NO_MAPPING, SENSORS_MODE_R, 
+                         SENSORS_NO_MAPPING, SENSORS_MODE_RW, 
                          W83781D_SYSCTL_FAN_DIV, VALUE(3), 0 },
     { SENSORS_W83782D_ALARMS, "alarms", SENSORS_NO_MAPPING, SENSORS_NO_MAPPING, 
                          SENSORS_MODE_R, W83781D_SYSCTL_ALARMS, VALUE(1), 0 },
@@ -1030,7 +1030,7 @@ static sensors_chip_feature w83782d_features[] =
                          SENSORS_NO_MAPPING, SENSORS_MODE_RW, 
                          W83781D_SYSCTL_FAN_DIV, VALUE(2), 0 },
     { SENSORS_W83782D_FAN3_DIV, "fan3_div", SENSORS_W83781D_FAN3, 
-                         SENSORS_NO_MAPPING, SENSORS_MODE_R, 
+                         SENSORS_NO_MAPPING, SENSORS_MODE_RW, 
                          W83781D_SYSCTL_FAN_DIV, VALUE(3), 0 },
     { SENSORS_W83782D_ALARMS, "alarms", SENSORS_NO_MAPPING, SENSORS_NO_MAPPING, 
                          SENSORS_MODE_R, W83781D_SYSCTL_ALARMS, VALUE(1), 0 },
@@ -1149,7 +1149,7 @@ static sensors_chip_feature w83783s_features[] =
                          SENSORS_NO_MAPPING, SENSORS_MODE_RW, 
                          W83781D_SYSCTL_FAN_DIV, VALUE(2), 0 },
     { SENSORS_W83783S_FAN3_DIV, "fan3_div", SENSORS_W83783S_FAN3, 
-                         SENSORS_NO_MAPPING, SENSORS_MODE_R, 
+                         SENSORS_NO_MAPPING, SENSORS_MODE_RW, 
                          W83781D_SYSCTL_FAN_DIV, VALUE(3), 0 },
     { SENSORS_W83783S_ALARMS, "alarms", SENSORS_NO_MAPPING, SENSORS_NO_MAPPING, 
                          SENSORS_MODE_R, W83781D_SYSCTL_ALARMS, VALUE(1), 0 },
@@ -2379,7 +2379,7 @@ static sensors_chip_feature it87_features[] =
                              SENSORS_MODE_RW, IT87_SYSCTL_FAN_DIV, VALUE(2),
                              0 },
     { SENSORS_IT87_FAN3_DIV, "fan3_div", SENSORS_IT87_FAN3, SENSORS_NO_MAPPING,
-                              SENSORS_MODE_R, IT87_SYSCTL_FAN_DIV, VALUE(3),
+                              SENSORS_MODE_RW, IT87_SYSCTL_FAN_DIV, VALUE(3),
                               0 },
     { SENSORS_IT87_ALARMS, "alarms", SENSORS_NO_MAPPING, SENSORS_NO_MAPPING,
                            SENSORS_MODE_R, IT87_SYSCTL_ALARMS, VALUE(1), 0 },