diff --git a/variants/DISCO_F100RB/variant.cpp b/variants/DISCO_F100RB/variant.cpp
index aeb9fd0b16..09a0d7675b 100644
--- a/variants/DISCO_F100RB/variant.cpp
+++ b/variants/DISCO_F100RB/variant.cpp
@@ -159,11 +159,11 @@ WEAK void SystemClock_Config(void)
   RCC_ClkInitTypeDef RCC_ClkInitStruct;
   RCC_PeriphCLKInitTypeDef PeriphClkInit;
 
-  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
-  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
-  RCC_OscInitStruct.HSICalibrationValue = 16;
+  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
+  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
+  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV2;
   RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
-  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI_DIV2;
+  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
   RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL6;
   if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
   {