diff --git a/right/src/init_peripherals.c b/right/src/init_peripherals.c
index 19cd3a4..ac45b64 100644
--- a/right/src/init_peripherals.c
+++ b/right/src/init_peripherals.c
@@ -60,6 +60,8 @@ void InitPeripherals(void)
     InitI2c();
     InitTestLed();
     LedPwm_Init();
+#ifndef LED_DRIVER_STRESS_TEST
     InitI2cWatchdog();
+#endif
     EEPROM_Init();
 }
diff --git a/right/src/led_display.c b/right/src/led_display.c
index 79095d7..05571c3 100644
--- a/right/src/led_display.c
+++ b/right/src/led_display.c
@@ -65,12 +65,12 @@ void LedDisplay_SetText(uint8_t length, const char* text) {
     case 1:
         allSegmentSets |= characterToSegmentSet(text[0]);
     }
-    LedDriverStates[LedDriverId_Left].ledValues[11] = allSegmentSets & 0b00000001 ? 255 : 0;
-    LedDriverStates[LedDriverId_Left].ledValues[12] = allSegmentSets & 0b00000010 ? 255 : 0;
+    LedDriverStates[LedDriverId_Left].sourceLedValues[11] = allSegmentSets & 0b00000001 ? 255 : 0;
+    LedDriverStates[LedDriverId_Left].sourceLedValues[12] = allSegmentSets & 0b00000010 ? 255 : 0;
     allSegmentSets >>= 2;
     for (uint8_t i = 24; i <= 136; i += 16) {
         for (uint8_t j = 0; j < 5; j++) {
-            LedDriverStates[LedDriverId_Left].ledValues[i + j] = allSegmentSets & 1 << j ? 255 : 0;
+            LedDriverStates[LedDriverId_Left].sourceLedValues[i + j] = allSegmentSets & 1 << j ? 255 : 0;
         }
         allSegmentSets >>= 5;
     }
@@ -79,13 +79,13 @@ void LedDisplay_SetText(uint8_t length, const char* text) {
 
 void LedDisplay_SetLayer(uint8_t layerId) {
     for (uint8_t i = 13; i <= 45; i += 16) {
-        LedDriverStates[LedDriverId_Left].ledValues[i] = 0;
+        LedDriverStates[LedDriverId_Left].sourceLedValues[i] = 0;
     }
     if (layerId >= LAYER_ID_MOD && layerId <= LAYER_ID_MOUSE) {
-        LedDriverStates[LedDriverId_Left].ledValues[16 * layerId - 3] = 255;
+        LedDriverStates[LedDriverId_Left].sourceLedValues[16 * layerId - 3] = 255;
     }
 }
 
 void LedDisplay_SetIcon(led_display_icon_t icon, bool isEnabled) {
-    LedDriverStates[LedDriverId_Left].ledValues[8 + icon] = isEnabled ? 255 : 0;
+    LedDriverStates[LedDriverId_Left].sourceLedValues[8 + icon] = isEnabled ? 255 : 0;
 }
diff --git a/right/src/slave_drivers/slave_driver_led_driver.c b/right/src/slave_drivers/slave_driver_led_driver.c
index 1b567c6..902f37e 100644
--- a/right/src/slave_drivers/slave_driver_led_driver.c
+++ b/right/src/slave_drivers/slave_driver_led_driver.c
@@ -63,6 +63,7 @@ void LedSlaveDriver_Init(uint8_t ledDriverId) {
     currentLedDriverState->phase = LedDriverPhase_SetFunctionFrame;
     currentLedDriverState->ledIndex = 0;
     LedDriverStates[LedDriverId_Left].setupLedControlRegistersCommand[7] |= 0b00000010; // Enable the LED of the ISO key.
+    memset(currentLedDriverState->targetLedValues, 0xff, LED_DRIVER_LED_COUNT);
     SetLeds(0xff);
     LedDisplay_SetText(3, "ABC");
 }
@@ -94,20 +95,66 @@ void LedSlaveDriver_Update(uint8_t ledDriverId) {
             *ledDriverPhase = LedDriverPhase_Initialized;
             break;
         case LedDriverPhase_Initialized:
+        {
+#ifdef LED_DRIVER_STRESS_TEST
             updatePwmRegistersBuffer[0] = FRAME_REGISTER_PWM_FIRST + *ledIndex;
-            memcpy(updatePwmRegistersBuffer+1, currentLedDriverState->ledValues + *ledIndex, PMW_REGISTER_UPDATE_CHUNK_SIZE);
+            memcpy(updatePwmRegistersBuffer+1, currentLedDriverState->sourceLedValues + *ledIndex, PMW_REGISTER_UPDATE_CHUNK_SIZE);
             I2cAsyncWrite(ledDriverAddress, updatePwmRegistersBuffer, PWM_REGISTER_BUFFER_LENGTH);
             *ledIndex += PMW_REGISTER_UPDATE_CHUNK_SIZE;
             if (*ledIndex >= LED_DRIVER_LED_COUNT) {
                 *ledIndex = 0;
             }
+#else
+            uint8_t *sourceLedValues = currentLedDriverState->sourceLedValues;
+            uint8_t *targetLedValues = currentLedDriverState->targetLedValues;
+
+            uint8_t lastLedChunkStartIndex = LED_DRIVER_LED_COUNT - PMW_REGISTER_UPDATE_CHUNK_SIZE;
+            uint8_t startLedIndex = *ledIndex > lastLedChunkStartIndex ? lastLedChunkStartIndex : *ledIndex;
+
+            uint8_t count;
+            for (count=0; count<LED_DRIVER_LED_COUNT; count++) {
+                if (sourceLedValues[startLedIndex] != targetLedValues[startLedIndex]) {
+                    break;
+                }
+
+                if (++startLedIndex >= LED_DRIVER_LED_COUNT) {
+                    startLedIndex = 0;
+                }
+            }
+
+            bool foundStartIndex = count < LED_DRIVER_LED_COUNT;
+            if (!foundStartIndex) {
+                *ledIndex = 0;
+                return;
+            }
+
+            uint8_t maxChunkSize = MIN(LED_DRIVER_LED_COUNT - startLedIndex, PMW_REGISTER_UPDATE_CHUNK_SIZE);
+            uint8_t maxEndLedIndex = startLedIndex + maxChunkSize - 1;
+            uint8_t endLedIndex = startLedIndex;
+            for (uint8_t index=startLedIndex; index<=maxEndLedIndex; index++) {
+                if (sourceLedValues[index] != targetLedValues[index]) {
+                    endLedIndex = index;
+                }
+            }
+
+            updatePwmRegistersBuffer[0] = FRAME_REGISTER_PWM_FIRST + startLedIndex;
+            uint8_t length = endLedIndex - startLedIndex + 1;
+            memcpy(updatePwmRegistersBuffer+1, currentLedDriverState->sourceLedValues + startLedIndex, length);
+            memcpy(currentLedDriverState->targetLedValues + startLedIndex, currentLedDriverState->sourceLedValues + startLedIndex, length);
+            I2cAsyncWrite(ledDriverAddress, updatePwmRegistersBuffer, length+1);
+            *ledIndex += length;
+            if (*ledIndex >= LED_DRIVER_LED_COUNT) {
+                *ledIndex = 0;
+            }
+#endif
             break;
+        }
     }
 }
 
 void SetLeds(uint8_t ledBrightness)
 {
     for (uint8_t i=0; i<LED_DRIVER_MAX_COUNT; i++) {
-        memset(&LedDriverStates[i].ledValues, ledBrightness, LED_DRIVER_LED_COUNT);
+        memset(&LedDriverStates[i].sourceLedValues, ledBrightness, LED_DRIVER_LED_COUNT);
     }
 }
diff --git a/right/src/slave_drivers/slave_driver_led_driver.h b/right/src/slave_drivers/slave_driver_led_driver.h
index 325f0cd..f728b6c 100644
--- a/right/src/slave_drivers/slave_driver_led_driver.h
+++ b/right/src/slave_drivers/slave_driver_led_driver.h
@@ -31,7 +31,8 @@
 
     typedef struct {
         led_driver_phase_t phase;
-        uint8_t ledValues[LED_DRIVER_LED_COUNT];
+        uint8_t sourceLedValues[LED_DRIVER_LED_COUNT];
+        uint8_t targetLedValues[LED_DRIVER_LED_COUNT];
         uint8_t ledIndex;
         uint8_t i2cAddress;
         uint8_t setupLedControlRegistersCommand[LED_CONTROL_REGISTERS_COMMAND_LENGTH];