diff --git a/demos/STM32/RT-VFS-FATFS/cfg/stm32g474re_nucleo64/mcuconf.h b/demos/STM32/RT-VFS-FATFS/cfg/stm32g474re_nucleo64/mcuconf.h
index 695ea0df0..f27fa82ec 100644
--- a/demos/STM32/RT-VFS-FATFS/cfg/stm32g474re_nucleo64/mcuconf.h
+++ b/demos/STM32/RT-VFS-FATFS/cfg/stm32g474re_nucleo64/mcuconf.h
@@ -75,7 +75,7 @@
 #define STM32_PLLQ_VALUE                    8
 #define STM32_PLLR_VALUE                    2
 #define STM32_HPRE                          STM32_HPRE_DIV1
-#define STM32_PPRE1                         STM32_PPRE1_DIV4
+#define STM32_PPRE1                         STM32_PPRE1_DIV2
 #define STM32_PPRE2                         STM32_PPRE2_DIV1
 #define STM32_MCOSEL                        STM32_MCOSEL_NOCLOCK
 #define STM32_MCOPRE                        STM32_MCOPRE_DIV1
diff --git a/demos/STM32/RT-VFS-FATFS/cfg/stm32g474re_nucleo64/portab.c b/demos/STM32/RT-VFS-FATFS/cfg/stm32g474re_nucleo64/portab.c
index 1a726be08..a8e0fceb1 100644
--- a/demos/STM32/RT-VFS-FATFS/cfg/stm32g474re_nucleo64/portab.c
+++ b/demos/STM32/RT-VFS-FATFS/cfg/stm32g474re_nucleo64/portab.c
@@ -51,7 +51,7 @@
 /*===========================================================================*/
 
 /* Making sure mcuconf.h setup is as expected.*/
-#if STM32_PCLK1 != 85000000/2
+#if STM32_PCLK1 != 85000000
 #error "unexpected PCLK1 frequency"
 #endif