diff --git a/main.c b/main.c
index 42477f8..b5ca93c 100644
--- a/main.c
+++ b/main.c
@@ -32,7 +32,7 @@ int main(void) {
 #if 0
   rcc_clock_setup_pll(&rcc_hse_25mhz_3v3[RCC_CLOCK_3V3_84MHZ]);
 #else
-  rcc_clock_setup_pll(&rcc_hse_12mhz_3v3[RCC_CLOCK_3V3_168MHZ]);
+  rcc_clock_setup_pll(&rcc_hse_12mhz_3v3[RCC_CLOCK_3V3_84MHZ]);
 #endif
 
   RINGBUFFER_INIT(uart_to_usb_buf, 64);