diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index 9ae51c9..b874995 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -3559,7 +3559,7 @@
  * comment in the specific module. */
 
 /* MPI / BIGNUM options */
-//#define MBEDTLS_MPI_WINDOW_SIZE            6 /**< Maximum window size used. */
+//#define MBEDTLS_MPI_WINDOW_SIZE            2 /**< Maximum window size used. */
 //#define MBEDTLS_MPI_MAX_SIZE            1024 /**< Maximum number of bytes for usable MPIs. */
 
 /* CTR_DRBG options */