diff --git a/platform/common/plat_sdl.c b/platform/common/plat_sdl.c
index cb02919b..79664c3d 100644
--- a/platform/common/plat_sdl.c
+++ b/platform/common/plat_sdl.c
@@ -191,7 +191,7 @@ void plat_video_flip(void)
 		g_screen_ptr = plat_sdl_screen->pixels;
 		plat_video_set_buffer(g_screen_ptr);
 		if (clear_buf_cnt) {
-			memset(g_screen_ptr, 0, plat_sdl_screen->w*plat_sdl_screen->h * 2);
+			memset(g_screen_ptr, 0, plat_sdl_screen->pitch*plat_sdl_screen->h);
 			clear_buf_cnt--;
 		}
 	}
@@ -225,7 +225,7 @@ void plat_video_clear_buffers(void)
 	if (plat_sdl_overlay || plat_sdl_gl_active)
 		memset(shadow_fb, 0, g_menuscreen_w * g_menuscreen_h * 2);
 	else {
-		memset(g_screen_ptr, 0, plat_sdl_screen->w*plat_sdl_screen->h * 2);
+		memset(g_screen_ptr, 0, plat_sdl_screen->pitch*plat_sdl_screen->h);
 		clear_buf_cnt = 3; // do it thrice in case of triple buffering
 	}
 }