diff --git a/src/main.c b/src/main.c
--- a/src/main.c
+++ b/src/main.c
@@ -99,6 +99,10 @@ int main(void)
             {
                 blink_rate = BLINK_SLOW;
                 HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+
                 // Wait for RTC wakeup interrupt
                 //wfi();
                 //enter_sleep();
@@ -112,6 +116,11 @@ int main(void)
             case SYSTEM_GPSACQ:
             {
                 blink_rate = BLINK_FAST;
+                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+
 
                 if(!gps_ison())
                 {
@@ -176,6 +185,13 @@ int main(void)
             			state = SYSTEM_IDLE;
             		}
                 }
+            	else
+            	{
+                    HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                    HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                    HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+                    HAL_PWR_EnterSLEEPMode(0, PWR_SLEEPENTRY_WFI);
+            	}
 
                 // Schedule next wakeup (maybe 2mins prior ot timeslot if no osc trim)
                 // Next wakeup should enter SYSTEM_GPSACQ state...
diff --git a/src/system.c b/src/system.c
--- a/src/system.c
+++ b/src/system.c
@@ -44,7 +44,7 @@ void sysclk_init(void)
     RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                                 |RCC_CLOCKTYPE_PCLK1;
     RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
-    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
+    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV4;
     RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
     HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0);